How to Fit Yoshimura ST-1 Cams
NOTE: This thread is also available to download as a PDF file from the Downloads (General) Section
This thread directly references fitting the Yoshi ST-1 cams, but broadly applies to any more extreme profiled cams in the 14 engine. This is not model specific, to my knowledge there's no difference across the models that affects this
First things first
1. Before stripping the motor down or reaching for the spanners, read these instructions together with the instructions you received from Yoshimura until you are sure about what you are about to do and the steps to be taken.
2. I've done this write up as a vague guide, and I'm doing it a few months after performing this procedure myself. There's every chance my memory has omitted some detail, if so, I can't be held responsible - this is a rough guide, not manufacturer’s instructions (see the workshop manual and cam instructions for those, they fully cover the job.
3. I think this is a detailed, yet fairly simple job. I'm not a trained mechanic but have replaced internals on a few bike engines before. You just have to be very methodical. Anyone who's fairly competent and confident with spanners should be able to manage this, so I'll rate it 3.5/5 for "how hard is it to do myself mate?" (1 being putting petrol in the tank - 5 being fitting new gears).
4. If you don't feel confident, get a mechanic who is.
5. Oh, one last thing... have fun, it's a nice job to perform
Things you should be aware of:
(a). The fueling will be off after fitting, and a PCIII and dyno setup is needed
(b). New cams will require running in
(c). You must check your shims after assembly, and it's quite likely your shims will need changing, especially on the intake side
(d). Not being funny here - the bike will pick up speed quicker in mid revs. Do consider uprating brakes and suspension first for safer riding (please)
(e). The Cam Journal Covers MUST be modified, to prevent the new profile cams hitting them and doing untold damage!
(f). This job will be easier on an empty tank - don't refuel just before you plan to do this
(g). You can fit the cams and perform all this without removing the engine from the frame (which is a bonus!)
(h). This is not a job that you should do over a few beers. Cams are best fitted when sober.
Things you really should have to hand before you start:
(a). Workshop manual
(b). At least half a day to perform the job
(c). Torque Wrench & a range of sockets, along with Allen keys, tray for storing all the bolts, selection of spanners and any other usual useful tools
(d). A fairly fine metal file
(e). Some fresh engine oil
(f). Some Moly grease (for prepping the cam lobes to be run in)
(g). A rear paddock stand is handy to level the bike and raise it a little, the centre stand would do
(h). Some instant gasket - to help re-fit the cam cover gasket (can be re-used so long as it's in good condition)
(i). Clean rags (Also some cleaner/polish/ACF50 is good to have around as you can clean up the top of the engine whilst you're accessing it
Ready? Here's roughly what you do:
1. Clean the bike first. Then remove seat & side panels
2. Disconnect fuel line & power couplings to underneath of tank.
3. Remove tank & place on blanket/cardboard to prevent damage Remove the rubber bungs from the frame that hold the tank (in case they fall into the engine)
4. Remove PAIR system (recommend you do the PAIR mod here and block off airbox outlet and use blanking plates on the engine side)
5. Clean top of engine to remove anything that could fall in, then disconnect and remove Cam Position sensor
6. Remove the Camchain tensioner from the rear side of the head, observing which way around it is as you remove it. It fits both ways, but must only go in the correct way - fiddly to get to and must come out straight or it can snag on the inside of the head
7. Disconnect and tie off the Plug caps & leads so they're out the way
8. Clean the bike of any debris that's around the top of the head, or anywhere over it. You don't want grit and other things landing on your exposed cams
Pause: Now have a cup of tea and something to eat. The next chunk should all be done in one hit to avoid leaving the engine exposed to dust and stupidity
REALLY, REALLY IMPORTANT NOTE: You MUST Follow the instructions in the workshop manual, and cross reference with the fitting instructions that come with the Cams for all the next steps
9. Remove all bolts, then remove the upper cover/cam cover from the engine, this will expose the cams. Be careful not to damage the gasket, and DO NOT pry anything. A simple, very light tap with a rubber mallet around the cam cover will loosen this enough to lift off by hand. If it doesn't move, you've overlooked a bolt.
10. You can now see the covers that retain and guide the camchain, and the camshafts. Carefully remove the camchain cover, making extra sure you don't lose the bolts inside the engine (particularly down the opening for the camchain). If you do lose something in there, unless you can recover it, it's potentially a full engine strip down which will easily take a day or two (engine out), and require more gaskets.
11. Camshaft Journal Covers coming out next. Note which goes where - they're all marked up. You remove them one at a time. Be aware that when you do get them off, the camshafts will be loose. This means they'll pop out of their journals, the camchain will come off/slip a few teeth, and your cam timing will go off... past the point of no return now!
12. Take a very long, clean screwdriver, or metal bar/pipe at least 10-12 inches in length. Slip this under the camchain, then remove each cam by lifting it out of the journals and towards the centre of the motor to slip it free of the tension from the chain. You screwdriver/bar is there to prevent the possibility of your cam chain falling into the motor and off the opposing wheel/cog at the base of the head.
13. Both cams are out. Fiddly job now. Remove the wheel/cog from each of your existing cams - these go onto your ST-1 cams. The bolts are 'you little ****er' tight, and you'll have fun figuring it out so I won't spoil this for you. Once off, fit them to your new cams, and ensure they're 'you little ****er' tight when you do so.. again, fun that. Just don't use a bloody vice to hold it! Note which wheel came from which cam and refit the same way around to match up for wear (easier to do one cam at a time - as in swap the intake one first, then exhaust after).
14. Half way there. Apply Moly grease to the journals and lobes of the new camshafts - the moly gets into the metal to protect, allowing them to bed in better.
15. Fit the new cams into place, ensuring you’re getting them in the right way around (intake on intake, exhaust on exhaust). Get that wrong and results cannot be predicted... but they probably aren't good.
16. Pick up your intake cam journal covers (the cover things with the holes in that you took off to let the original cams out). On the intake covers, file a deep groove into the depressed notches that are by the holes - according to Pops Yoshimura, these indents will be hit by your cams if left untouched. You're looking to lose about 3-4mm, as per the pictures in the cam instruction leaflet that's in the Yoshi box when delivered.
17. IMPORTANT: Observe the notes on aligning the timing marks on your camshaft wheels, and also on resetting the camchain correctly. You must count exactly the right number of camchain link pins between the two marks. Get that wrong, or do so when the markings are not aligned correctly and your cam timing will be out. I know that on a lot of engines that will introduce Mr Piston and Mr Valve.. and you then get known as "Mr Engine Rebuild" to your mates.
18. So, new cams in, cam timing set.. easy from here. Replace the Journal covers over both cams. Torque them down gently, alternating between the covers to lower the cams evenly (not one cover all the way in at a time). Use diagonally opposing bolts across each cover as you lower it, so as to lower the journal covers evenly too. Everything wants to go down straight an level, not one corner or part at a time. These will force the cams into place and gather some tension on the 'now correctly timed' area of the chain. The tensioner then removes the running slack in the rest of it later.
NOTE: NOW DOUBLE AND TRIPLE CHECK THAT YOUR TIMING IS RIGHT, AND YOU'VE GOT THE CAMS IN THE RIGHT SIDES OF THE MOTOR
19. Replace Camchain Cover (don't lose those bolts into the motor!)
20. Pour fresh engine oil into the pocket of each cam lobe (recess of the head that holds the cam-lobe and shim), covering the lobe and the shims as deeply as the pockets allow. Ensure you get all of these or you'll start the motor with a dry cam, and that's not very friendly.
21. Now that you've observed the 3-part action of stage 20 to prevent wrecking the pistons, you can relax and continue
22. Replace the Camchain Tensioner, ensuring you get it the right way up (if its in right way up and upside down) - the teeth on the spring loaded shaft must face downwards. Wrong way round and there's a chance it could ratchet back in and let the camchain jump off the wheels whilst running (see previous point about Mr Piston and Mr Valve again). This is the fiddly little **** of a task that will likely take you 3-hours of skinned knuckle swearing - again, I won't spoil the fun, you'll figure it out (hint, use ring spanners)
23. Right, your back will probably be hurting from hunching over the motor. Camchain tensioner's bolted in, camchain's under tension, timing's correct, cam journal covers are in place. Brilliant, worst of it done. Quickly check your valve clearances, or take the bike to your dealer from them to do it (after you've assembled the bike obviously - cost around £70 for labour and swapping shims, or about £60 to buy shims yourself).
24. Replace the cam cover, using a little instant gasket to help seat it (and I mean a really thin smear, not a thick smear, or a bead of it you oil journal blocker!) observe guidelines for the order in which to torque it down, and correct torque settings. Replace Cam Position sensor too.
25. Reassemble everything else, according to the way it came apart - use the workshop manual or photos you took during disassembly if you can't remember.
26. Once all refitted and reconnected... stand up and beat your chest like the real man you are, you've just fitted racing cams to your 1402cc bike, without a mechanic!
27. Here, I loaded the "Akra system and Yoshi ST1 Cams" PowerCommander map onto my PCII. Not perfect as mine's a Yoshi system, but it's closer than stock fueling. Please get to a Dyno ASAP for setup
28. Start the motor (don't rev it!!!!), and listen to the engine for knocks or nasty noises. You'll hear the camchain whirr, and the ticking of the cams. You shouldn't hear anything else nasty. If you do stop, disassemble for idiot checks, or hand it to a competent mechanic.. then hand your spanners into the police station and have yourself put on the offenders list of people never to buy bikes from.
29. Observe the detailed bedding in procedure for the cams that are in the instructions they came with, it outlines rev limits and distances they're imposed for. Don't go out and hammer it you loon!
Additional comments made after the above was posted
Response-1
I have just finished mine this evening I reckon it took 5 hours taking it easy. The bike only has 1100 miles on it so nothing was corroded on.
I took off the coils for better access and undid the 2 bolts holding the oil cooler on so it can be pushed forward a little for better clearance for removing the cam cover.
The only extra I did was put thread lock on the bolts holding the cam gears. You can put the cam gears in the vice for undoing and tightening using soft jaws that’s the best way I could find to hold them.
Before starting and putting the tank back on I unplugged the coils and cranked it over on the starter for a while to get the oil pressure up.
I did the inlet cam first and put the chain back on and held it in place with a cable tie so when installing the exhaust cam I only had to count 24 rollers so it was in the correct place.
The cam journals cover were really tight I couldn’t them pull the off so I put a drift down one of the mounting holes that was the exact same size one little wiggle and it was loose don’t lose the little dowels that are on the covers put them straight back in the hole on the engine.
I must have checked the alignment of the cams and cam chain about 5 times just to make sure.
Response from Topic Author
There's a pic of where to modify them in the Yoshi instructions that come with the cams (see end of this article). I used a medium/fine grade file to modify the covers. In the covers, there is a hole and indent either side. On the inside of the cover, it's that indent you're filing down to gain more lobe clearance.
Response-2
Most aftermarket cam makers state you mustn't let the engine idle for an excessive amount of time. That's because the cam lobes get a limited amount of oil at idle. A few revs raises the pressure to give more fed oil and splash oil.
Lobes are "soft" when new and it is the running in that hardens them.
If you go too hard too soon you stand a good chance of knocking a lobe off or severely damaging one by flattening it.
Response-3
I think you will find the cams are case hardened then ground to size, the reason for running in is so that the new cam gradually wears its self into the new bearing material
Response-4
Here are the pictures. May be quantity is a little bit more than you need
(https://gsx1400owners.org/forum/gallery/0/9-050217021042-1372411.jpeg)
(https://gsx1400owners.org/forum/gallery/0/9-050217021034-1311931.jpeg)
(https://gsx1400owners.org/forum/gallery/0/9-050217021034-1311394.jpeg)
(https://gsx1400owners.org/forum/gallery/0/9-050217021036-1332088.jpeg)
(https://gsx1400owners.org/forum/gallery/0/9-050217021038-1341937.jpeg)
Response-5
I'd like to point out that every engine is individual with different clearances and when changing to high-lift cams you have to check all the spots where the clearances might be too small.
In my engine the intake covers were good, only one spot had to be filed but several valve holes were too close to the cam and the cam hit the valve head itself. It's very important to check that the cams are not touching anything else but the valve caps and that’s a bit hard to do if you have the valve head attached in motor (with the valve caps in place).
Just wanted to point out that it's very important to check all the possible spots where the cam might get in touch to avoid engine break down.
(https://gsx1400owners.org/forum/gallery/0/9-050217021040-1351739.jpeg)
(https://gsx1400owners.org/forum/gallery/0/9-050217021040-135701.jpeg)
So fitted Yoshi camshaft today and measure valves clearences.
Standard manual says:
IN: 0,10 - 0,20 mm
EX: 0,20 - 0,30 mm
Yoshi manual says:
IN: 0,18 - 0,22 mm
EX: 0,23 - 0,27 mm
After fitted Yoshi camshaft I have this valves clearences:
IN: 0,88 - 0,97 mm
EX: 0,44 - 0,52
I know that after fitting Yoshi camshaft valve clearences are off. But so many off? :confused1: Is it normal? :confused1: Please reassure me that this is normal.
that sounds big gaps
but i didn't fit my yoshi cams as my local bike shop did it cheaper than i could have
so i don't know what shims they used .
hopefully other have a better idea
sorry i couldn't help buddy :frustrated:
Hi
@V_i_c_i What about your cams? Have you done a dyno setup? Any charts to share? Or at least your impression of them?
Hi Northern
Yoshi camshaft fitted, valve clearences done and AFR table set. But due to bad weather or lack of time (I´m reconstructing the house and my old bike M-72 from 1952 need differential overhaul) done just 150km from break in procedure. Need do 150km more, check valve clearances again and than will go to dyno.
So just one good new is that PC V + autotune works great. :onya:
BR Vici
@V_i_c_i Will be very interested to see dyno chart. Hope you post it here
Quote from: V_i_c_i on Tuesday, 28 February 2017, 07:31 AM
So fitted Yoshi camshaft today and measure valves clearences.
Standard manual says:
IN: 0,10 - 0,20 mm
EX: 0,20 - 0,30 mm
Yoshi manual says:
IN: 0,18 - 0,22 mm
EX: 0,23 - 0,27 mm
After fitted Yoshi camshaft I have this valves clearences:
IN: 0,88 - 0,97 mm
EX: 0,44 - 0,52
I know that after fitting Yoshi camshaft valve clearences are off. But so many off? :confused1: Is it normal? :confused1: Please reassure me that this is normal.
@V_i_c_i Just finish measuring valve clearance after fitting new cams:
EX (left to right) 0,28 0,26 0,26 0,27 0,28 0,27 0,26 0,30
IN (left to right) 0,15 0,16 0,14 0,17 0,19 0,18 0,18 0,18
Seems like 3 and 4 will not need intake adjustments in my case.
Looks to me like you switched (when typing) IN and EX.
By left to right you mean by looking at cylinders from front?
You put in Yoshi camshaft?
Quote from: Andre on Wednesday, 31 January 2018, 07:34 AM
Looks to me like you switched (when typing) IN and EX.
By left to right you mean by looking at cylinders from front?
You put in Yoshi camshaft?
@Andre Good point! But now typo is corrected :)
Left to right - from cylinder 1 to cylinder 4
Yoshis were in, but at exact moment they are out again :). Work in progress. Tomorrow will try to purchase new shims, and may be Thursday will find time to put them permanently in....
If only I will get RED LINE ASSEMBLY LUBE https://www.redlineoil.com/assembly-lube (https://www.redlineoil.com/assembly-lube) (shipped 2 weeks ago from just 600km away :furious:).
Has anybody measured lobe center degrees from yoshi ST- 1 or std cams? Yoshi ST-1 brochure says 105/105 degrees, but measured degrees? How about lobe centers of std cams with std sprockets?
@T 24 Mine engine cylinder head is still open, cause I don't have time to check adjusted valve clearances and tomorrow I'm going to bussines trip... But next weekend, I'm planning to finish the job, so I may tray to measure them - if you find me simple instruction how to do this :)
Not sure, how accurate it will be, but I could give it a try...
@ northern
Here is some instructions for you and for everybody. Helps to understand how camshaft works.
http://www.webcamshafts.com/index_blank.html?pages/degreeing.html
http://www.lunatipower.com/Tech/Cams/CamSpecTerms.aspx
Finally I'm happy with valve clearances:
EX (left to right) 0,26 0,26 0,25 0,26 0,25 0,26 0,25 0,26
IN (left to right) 0,21 0,22 0,21 0,21 0,20 0,21 0,21 0,22
You have made exellent work with your clearances!
Well done mate, youre a patient man. Top job
So after all the buggerisizing around... how does it go? :cheers:
So fare not really fast... :grin:
Engine is still of the bike - I have ~2 months, before weather would allow me to go for a ride.
First ~500-1000 km I would try to go easy on the engine, to brake-in new cams. Then oil and filter change and after that dyno tuning and measurements.
In the middle of the July, there is streetfighter bike rally, where is open drag strip with proper telemetry. After that I will answer your question :hat:
Ok, I know this is not Yoshi thing, but cam swap anyway...
I changed my std exhaust cam to std intake cam, to get more lift and duration to exhaust side for my turbo application. Now I have symmetrical cams.
I also fitted adjustable cam sprockets to both cams. I made them from old cam sprockets by milling long holes.
Also I had to make new timing marks to exhaust sprocket.
Lobe centers I set to 110°/110°.
With valve clearances was easy, because the base circle is the same in all std safts. All exhaust clearances were between 0.24 and 0.26mm and intake 0.11 to 0.12mm.
I did nothing to them.
Only small problem was the weather: this morning there was -24°c in my garage. Tools were cold...
-24 FFS!!! Jeez, can't you move to a warmer climate? My Freezer only runs at -18 - -20!
We were sayin the other day how 'hard' the Aussies' are, reckon you've just taken the cake there T24! No competition. :onya:
@T 24good engineering. Would be interesting to know, how will it affect performance.
Almost the same answer than yours northern, about two months, then I can start testing..
But this same swap is commonly used in turbo hayabusas and it works, giving 20-40 hp more with the same boost (in busa).
And about 10 hp in N/A engine (busa).
Just found this email thought it was lost as it was on the old org.
Its a comparison between yoshi st1 cams.
And a regrind of standard cams by Kent cams.
Both give very simular high bhp and torque numbers
Both bikes were ran on the same dyno on the same day so is a very good comparison.
The yoshi's are blue lines and Kent cams the red.
Both bikes felt great on the road but the yoshi cams pulled much stronger in the mid range where you acctully ride the bike as seen in the graph
My graph is now even smoother as it was re-dynoed after fitting the pod filters but no extra bhp .
@seth. You may be correct with that comparison and probably you are.
But unfortunately nothing is so simple.
Those two bikes, did they have the same exhaust system? Air filter? Fueling, PC, maps? Age, 16 or 32 bit ecu?
Cam lobe center settings?
We know that stock yoshi has 105/105°, what Kent Cams they were and what timing?
I can see, there are small differences on AFR curves.
Couple of years ago Mr. Jack Frost from Holeshot Racing told me that the huge difference between their GSX 1400 stage 1 and stage 2
turbo kits comes only from cams, 200/250 RWHP, and Kent Cams is making those cams.
https://www.holeshotracing.online/pdf/turbo-pricelist/tbikesuzgsx1400_160924.pdf
Then Mr.Tony Woodward from Kent Cams told me what they are and what are the lobe centers.
I told him my own suggestion and his opinion was that it will work, but he can't give me any timing advises,
because there is no timing marks for that cam and the job has to be done by using dial indicators.
And it really works! I don't know the numbers, but it works!
So nothing is so simple.
Hiya
Both bike were running very simular set ups both were k6's (same airfilters and same pc111 usb) only differences were I had and akroprovic the other bike a yoshi exhaust and both ran custom maps to suit that were set up on the same dyno
Timing for both sets of cams was standard both cam sprockets were standard and unmodified .
The slight dip you see in the Kent cam graph mid range also transferred to the road where in a totally unscientific test we did rolling full throttle acceleration test from 30mph and 40mph my bike pulled much stronger.
We swopped bikes to ride and the test were the same my yoshi bike pulled stronger when Mike was riding it.
Both bikes felt smooth and pulled much better and felt lots more responsive than a full standard bike (emma's gsx1400) when ridden back to back with it.
The main thing is just to show differences between regrind of standard cams and yoshi cams .
The main thing was with Kent cams being a regrind of the standard cams the lobes were much smaller with different profiles to standard with the higher lift being managed by using much thicker shims .
Hope that explains what I was trying to show.
I've also seen where guys with turbo motors are using exhaust cams as inlet cams and getting a good amount of extra bhp I'd be very interested in finding out how and what it achieved as if it's all very topend bhp gains it not really what I'm looking for.
I think I said in my post that once you start going very quick on a gsx1400 the handling goes to pot very quickly .
My bike is mainly about the extra bhp and torque in the lower and mid ranges where the bike is mostly ridden and the benefits of all the work are most useable in the real world on normal roads while keeping the bike as user friendly and reliable as possible .
:cheers:
I understood your point. And I believe you are correct in that Yoshi vs. Kent thing.
I just tried to tell, that there can be so many things that matters, making comparison difficult.
Your road test, with changing riders, tells all we need to know
( if you had the same number of teeth in your sprockets, and i think you had)
Yes both bikes were running standard suzuki chains and sprockets at the time both bikes were at about 6000miles from new.
So many things change
I.E.
Same bike on same dyno on different days depending on atmospheric conditions give very different power outputs though I belive the graphs are quiet simular in shape.
I put my bike on a dyno in Denmark a whole ago and it had 140bhp but my mates standard 1250 bandit had 105bhp they only come with 98bhp and the guy said if it broke 100bhp we'd get a free beer.
So it was obviously reading slightly high ( not a bad thing when promoting your tuning business).but ok if all the bikes are running on the same dyno then they all run slightly higher or lower figure depending on how the dyno is set up and reading.
The guy who we were at (HMD dynos in cromarty in the highlands of scotland) says he has had so many bike from south dyno's up to tune/set up that have slightly lower readings on his dyno they get annoyed but are happy there bikes ride much better and then give the higher figures when back on the dyno's down south .
:cheers:
I know, there are big differences between dynos.
I have 116 hp and 134 nm in my dyno papers (and in my MOT papers too), and I'm happy with it. It's enough for me ;)
Irrespective of how much horsepower your bike produces, the truth is if you don't rev it to that point all the time it's more about the torque your bike produces that fires you out of the corners. Those who ride GSX1400 are only to well aware of the way they pull from low revs all the way to redline. :notworthy: :stir:
Does anyone know the full specs of the stock cams and/or the yoshi cams?
Very interested to know durqtion, advertised duration, and .050"/1mm lift.
Quote from: Shifty on Sunday, 26 May 2019, 05:29 PM
Does anyone know the full specs of the stock cams and/or the yoshi cams?
Very interested to know durqtion, advertised duration, and .050"/1mm lift.
Is this what you are after?
https://shop.yoshimura-jp.com/en/product/syousai.php?id=871
Quote from: T 24 on Monday, 05 February 2018, 02:17 AM
Has anybody measured lobe center degrees from yoshi ST- 1 or std cams? Yoshi ST-1 brochure says 105/105 degrees, but measured degrees? How about lobe centers of std cams with std sprockets?
You got the point! I did check the oem LC number is 100/103.5. If you just bolt on the ST-1 Yoshi camshat, you will find out it is far away off from the recommended LC 105/105! You have to redegree it for the recommendation setup properly. But it is not easy for DIY, please consult to ur mechanic or experienced engine builder. Don't be shy!
PS. As I know most of people just bolt it on without degreeing, engine runs without problem but not in a proper initial setup!
After installed, it revs from mid to high with linear power output and reduce engine brake a lot!
Not sure if this is a dumb question. Would the standard cams be dialled in perfectly, from the factory
Quote from: grog on Monday, 02 December 2019, 05:15 PM
Not sure if this is a dumb question. Would the standard cams be dialled in perfectly, from the factory
There are no dumb questions.
Standard cams are in standard position, and they aren't able to adjust with standard, unmodified, sprockets.
The timing can vary a bit, when the timing chain is wearing or the cylinder head surface has been grind.
Timing of my standard cams was 99°/104°, if I can remember correct.
Quote from: elderhome on Monday, 02 December 2019, 08:11 AM
Quote from: T 24 on Monday, 05 February 2018, 02:17 AM
Has anybody measured lobe center degrees from yoshi ST- 1 or std cams? Yoshi ST-1 brochure says 105/105 degrees, but measured degrees? How about lobe centers of std cams with std sprockets?
You got the point! I did check the oem LC number is 100/103.5. If you just bolt on the ST-1 Yoshi camshat, you will find out it is far away off from the recommended LC 105/105! You have to redegree it for the recommendation setup properly. But it is not easy for DIY, please consult to ur mechanic or experienced engine builder. Don't be shy!
PS. As I know most of people just bolt it on without degreeing, engine runs without problem but not in a proper initial setup!
After installed, it revs from mid to high with linear power output and reduce engine brake a lot!
Hi! Do you remember how far from 105° the ST1 cam was at drop in? (did you have to adjust forward or backwards...?)
Getting Yoshi cams fitted soon also. Is the running in time of just 300km enough...?
That's approx 180 odd miles and when running them in and keeping it under the revs as stated,will the bike still run fairly ok even tho the fuelling will be out etc..?
:smile2:
500 miles total varied rpm but with these as a soft max revs
200 below 3000 rpm
200 below 4000 rpm
100 below 5000 rpm
Then an oil and filter change and dyno
Then full power available .
Not the law but this Is what I did and now got 30000 miles on mine since.
Did my clearances today with yoshi st1 cams fitted
Left to right
Ex. 22 30. 20 22. 20 22. 22. 20
In. 17. 17. 17. 17. 20. 20 22. 22
Does any one have the correct clearances for the yoshi cams
According to the pic of the instructions that come with the Yoshi cams in the first post on this thread...
0.18-0.22mm Intake
0.23-0.27mm Exhaust
From memory that's a touch wider than standard cams, so you'd expect a little more top end noise once it's running on them.
Cams have been in since 2002. When crescent Suzuki built engine , it just started making a ticking noise a bit louder than usual
Hi
I purchased a set of Yoshi ST-1 cams for my K6 a couple of years ago but never got around to fitting them. Hopefully I am planning to get it done in the next week or two when i have time.
I have a couple of questions though please.
The label on the box the cams came in shows part number 211-114-0100 for K1-K5 models. There are cam sets listed on Ebay for bikes between 2001-2008, so I'm presuming that the cams never changed through the years and that the Yoshi set I have will work with my K6, even though the label only shows up to K5?
I'm anticipating a drop in the fuel economy of the bike. Will this be a significant drop please? I currently get about 45 mpg, getting approx 170-180 miles to a tank, don't use the higher revs that often, so i may decide against fitting them if the fuel consumption would be worsened drastically.
The bike setup includes a full Akrapovic with a shortened can, power commander 5 and autotune. I had welded a bung in the exhaust for the autotune sensor. The Power commander has had the map for the exhaust downloaded to it and i will download the map for the exhaust and st-1 cams, with the autotune doing any trimming in real time, so that should sort out the fuelling setup after. I have also already blanked the Pairs valves previously and may advance the timing by 2 degrees.
I have found the information in this thread useful and have a factory manual, so should be ok fitting them myself.
Thanks for your thoughts and replies
Kristen, hi.
As far as I know the valve train is the same for all model years, so the Yoshi cams should fit. Others with more in depth knowledge will chime in I'm sure. Your fuel economy will suffer, but the performance gain of these St1 cams and grin-factor should make it worthwhile.
Watching this with interest....
I have the same set up
I can Confirm the cams are the same across all years .
Once run in and remapped they ride like a normal bike till you open the throttle.
Below 4000 rpm you'll get good mpg that's legal road speeds (I have had 200+ miles from my yoshi bike tank while touring in europe)
I have a map for a pc3 usb that would work well for running in on your bike but would highly recommend a proper dyno run and remap as soon as the 500miles is completed.
Webike Japan has a runout deal on these, cheapest I've seen these ST1.
YOSHIMURA : [Closeout Product]Camshaft [ST-1][special price] [211-114-0100] (webike.net)
https://japan.webike.net/products/117469.html
Thank you Eric and Seth for your replies.
For general riding i'm changing up between about 2.5-3.5k, don't go above 4 or 5 often and can't remember the last time i went wide open throttle. Usually the times when i may open it up in a lower gear like 3rd or 4th is when joining a motorway or dual carriageway from the slip road.
So if my fuel consumption wont suffer badly for normal riding then i will try them, i can always put the standards back in if i think it's excessive and im stopping for fuel too often.
New chain and sprockets arrived yesterday and front brake discs coming monday, so that's the priority for the moment. Rear teeth are wearing and a clicking from the front due to warped discs and the pads moving back and forth, resulting in fluctuating brake force, advised on the last mot. Better to get the braking sorted before making the bike faster lol.
Quote from: Kristen on Sunday, 14 July 2024, 05:24 PMThank you Eric and Seth for your replies.
For general riding i'm changing up between about 2.5-3.5k, don't go above 4 or 5 often and can't remember the last time i went wide open throttle. Usually the times when i may open it up in a lower gear like 3rd or 4th is when joining a motorway or dual carriageway from the slip road.
So if my fuel consumption wont suffer badly for normal riding then i will try them, i can always put the standards back in if i think it's excessive and im stopping for fuel too often.
New chain and sprockets arrived yesterday and front brake discs coming monday, so that's the priority for the moment. Rear teeth are wearing and a clicking from the front due to warped discs and the pads moving back and forth, resulting in fluctuating brake force, advised on the last mot. Better to get the braking sorted before making the bike faster lol.
For your clicking brakes check the big spring on the top of the calipers (that's held on by the 2 small screws on each caliper) as they settle and can let the pads move about.
Give them a slight bend in the same direction as the original bends and see as this can often fix a clicking brake .
Good luck
Thanks for your idea about the brakes Seth. A couple of weeks ago I rebuilt the forks with new tubes and seals. While the callipers were off and the wheel was free to spin i could see the discs going in and out as they turned and the pads on the left side went in and out, the outer one clicking out at the same point each turn. Then while the wheel was off I removed the discs and cleaned up the mounting faces and refitted then, but it made no difference. The new discs should be here tomorrow so hopefully I'll get them on if it's dry.
I've just changed the chain and sprockets this evening. I thought the rear teeth were looking a little worn and the chain had recently gone slack and noisy, which prompted me to change them out. I've not changed them in the three years I've had the bike which is now at 30k and unless they were changed in the first 12k before i owned it, they were still the originals on there. When i took it apart the teeth on the front sprocket were starting to hook over and the spline was worn. The nut was looser than it should have been also. The chain hadn't stretched, but the rollers were worn and it had a bit of sideways bending. So they definitely needed doing.
Hopefully I'll be able to think about the cams again towards the end of the week, though maybe next week, as I'll be using the bike at the weekend camping and i don't want it off the road while i wait for replacement shims. Regarding the shims, I'm under the impression they are 7.48 (7.5) mm diameter ones.
I have clicking from the calibers, since new pads and EBC discs - was worried new discs warped as Mick had that problem with EBC - will try the spring bending - cheers Seth
@Seth
:redcard: :redcard:
ALL can we continue this conversation in another thread please, this thread is about fitting cams, not chains or brakes etc thanks.
Keep setting shims, start bike no problem, after a wee bit ticking starts to come and progressively getting louder,stop strip down and retakeshim gaps once engine cold no1 cylinder exhaust vale alternatively going from .27 to .30 or .33 any ideas
nobby, very strange.No clues from me,usually set and forget. Bearings all tightened, no prob with thread etc.Does cam face look ok? Pretty simple so cant think of other reasons
Checked ya shims are flat, one might be slightly not flat & adjusting the gap as it spins
I was thinking maybe the valve seat in the head is badly carboned up, each time the valve closes, a bit of carbon comes off, changing the tappet clearance, then builds up again, changing the gap again.
Eric, carbon building up would increase clearance, cam over valve. Something wrong with this scenario, just doesnt make sense.
Quote from: grog on Tuesday, 24 September 2024, 06:21 PMEric, carbon building up would increase clearance, cam over valve. Something wrong with this scenario, just doesnt make sense.
yep, and that's what was posted: 0.27 to 0.30 to 0.33. What about a soft valve seat? But then clearance would decrease...
Quote from: nobby68 on Monday, 23 September 2024, 04:38 AMalternatively going from .27 to .30 or .33
Alternatively and
or is what puzzles me!