GSX1400 Owners .org

Technically Speaking => Engine & Gearbox => Topic started by: BlackAdder on Saturday, 11 March 2017, 01:53 PM

Title: 2nd gear issue
Post by: BlackAdder on Saturday, 11 March 2017, 01:53 PM
...the problem that led me to this community in the first place...

I did write about it back at 2012 but... ...I managed to save it, so here you go:




Some of us has experienced the second gear issue, some of us has heard about it and some wonder if they have it too. I thought to briefly show whats broken from the gear box when it happens.

Im building my bikes gearbox for the second (and hopefully last) time now so I think that I know somehow the symptoms and the annoyment of the problem. In my bike (k7 model that is) it first felt like the engine would be cutting off at the peak torque range every now and then - the engine felt like it would be cutting off and on (that is how I FELT it) and after it became worse it was quite clear that the gears were fckt. That was the first time.

The second time I knew right away what was the issue but sense the driving season was just starting I just kept riding, usually just skipping the 2nd gear and changing straight to 3rd when accelerating. Have I'd been a bit more gentle with the trhottle, I would'nt had to change also the 3rd gears driven erm, spocket.

So, 2nd and 6th gear are both engaged when you have 2nd gear on. All the power comes "thorough" 6th gears sprockets where the second gears sprockets attach (the two most left sprockets, 2nd gear engaged):


(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F533d03f1aa467edcc6c6b3db2c6bbc0d%2Ftumblr_oa97rb3Or61va6rxno3_1280.jpg&hash=b2f3014f5211d4942286e8f907df2e2480758cd4)


(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2Fb4d8aee4e0f5c6d5ff582f0465e245e9%2Ftumblr_oa97noG03D1va6rxno3_1280.jpg&hash=18554f15bafbaf67716a95d714fc3504da4e68e1)



There's the 2nd and 6th driven gears, on the axle where the front sprocket attaches. The smaller sprocket "locks" to the small windows in the larger spocket. On the earlyer 1400's these where made form a bit different material and so some of them had the gearbox problem more often. In the later models it was fixed but still some got broken, along with mine. Two times.

Anyhow, whilst accelerating, especially when shifting without clutch, these parts wear and when they start to be round the 2nd gear dont lock as well anymore and starts to bounce. And now we have a problem that just gets worse every time it happens.

After the gears bounces for the first time it does some damage to the gear shifting forks (they move the gears in right positions when changing gears). The gearshifter fork bends a bit and starts to wear too. After a while it looks like this:

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2Fb7ae02d0d861bb4d1164ec56a069f2cf%2Ftumblr_oa97rb3Or61va6rxno2_1280.jpg&hash=b2eb79348067d413ad9ba794bc6d180a8f117e01)

And one doesent have to be a rocket scientist to figure out that this makes the problem even worse. Added to this there's allso the axle where the gear shifter forks moves - it might bend as well and that leads to a situation where the second gear doesent keep engaged at all. This happens actually quite fast from the first "whattahellwasthat" moment.

Cure

Undercutting the gears.

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F49928f01cdb61ba4994ac7c20e700943%2Ftumblr_oa97noG03D1va6rxno4_1280.jpg&hash=4fe454fc0ff8a7bc0550ce0250e8bde38a0b0909)

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F728fc2b07340aa57cf3f9e9c74c4a59b%2Ftumblr_oa97noG03D1va6rxno6_1280.jpg&hash=45b93bd43499f8d27ba3a4c0c962f9c982498025)

In most cases there are no other damages to the engine exept the 2/6 gears, gearshifter forks and the tubes (referring the axels as tubes as they are not solid) where the gearshifter forks slides around. You can also use the old sprockets after they have been machined, undercutted as those in the picture above. The idea is to machine the slots in small angles so that when the gear is engaged it will hold better. Suzuki did it the first time with -92 GSXR 1100 to keep the gearbox from pulling a part. In 1400 other gears are undercutted (looks a bit like a fishtail, look at the pic below, uncut sprocket at the right)

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F2411c9ad2a3f33c414aef545ad5bcb0b%2Ftumblr_oa97noG03D1va6rxno5_1280.jpg&hash=eb150d4b7ad0059ca1cb86372ba3b5859f6c4b89)


but the 2nd gear is left alone to help in finding neutral. When you have undercutted gears (especially if you have similar than the sprocket above, it has up- and downcut, or a full "race cut", to hold the gears allso during engine brake - not that usefull or necessary on a road bike...) you might have to change to 1st gear first and then up to get neutral.

The other thing is to change the gearshifterforktubes to heavyer ones that dont bend that easily:

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F98f5af17746b1636237ca6a187afd0e6%2Ftumblr_oa97lq4yRC1va6rxno9_1280.jpg&hash=560bc25564ed13b38ea23ed5865bcdc6dc5f27e9)

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F055a5d7938de1c9d45bc3c0a3b53a8d4%2Ftumblr_oa97lq4yRC1va6rxno10_1280.jpg&hash=17039f05028a8e08efa4ebe7f769ed54ba43660a)



OEM tube at the left, APE raceparts axels (1st Gen Busa performance parts for drag strip) at the center and right, you can see the difference. They wont bend so it shoud make a difference in gear shifting and the lifespan of the shifterforks.

Interesting part is that most of 1st gen hayabusas gearparts will fit to GSX. If one wants to change gear ratios for example, you could take a look what there is for hayabusa. The whole race gearbox is a bit expensive though, but its there.




While doing your fixing, order a set of new bolts for the cases and use the torque wrench. Them bolts doesnt take loosening and tightening that well, at least multiple times. It's way cheaper and faster than having a bolt snapping in the engine halves:

(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2Fca79adbc57b01288c0164cef8517d5c3%2Ftumblr_oa97vgnZm41va6rxno3_1280.jpg&hash=a7c1ad38f380b23cff8be50615db4c430e31c949)
 
(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F99975f90da49cc6203d192f0141eb432%2Ftumblr_oa97vgnZm41va6rxno4_1280.jpg&hash=e2706cb422ae1d906f828f630a4b5117c4a823c5)

...and check that the geaxbox axle bearings are in the right position (the holes line up with the retainer studs) to avoid further delays...


(https://gsx1400owners.org/forum/proxy.php?request=http%3A%2F%2F68.media.tumblr.com%2F71d84babd930a8095bff21a92315ecc8%2Ftumblr_oa981pvY341va6rxno1_1280.jpg&hash=691f7a9f8692a5541e0b25bbf6bec646baa29a6e)

Good news is that you can fix all of that. 







The parts needed as follows



(2nd driven gear 93,44â,¬ if you cant get the original undercutted)

2432124F00000


(6th driven gear 109,19â,¬ same thing with this one)
2436124F20000

Gear shifter forks 82,52â,¬ / piece, two needed
2521124F10000

The third gear shifter fork 83,37â,¬ one needed
2523124F20000


And if you want to go all-in:

Billet shift shafts:
Billet Shift Shaft Kit Suzuki Hayabusa 1999-2016 (APE Raceparts TSSH1300 or Brock's Performance)

Heavy duty driven axle:
Hayabusa Billet H/Duty Output Shaft (nova 002 or Robinson industries)

and your transmission should be bomb proof after those.



Hope this helps somebody.



Cheers,

BA
Title: Re: 2nd gear issue
Post by: gsxbarmy on Saturday, 11 March 2017, 04:23 PM
Top write up - thanks BA! (I've stickied this as well)
Title: Re: 2nd gear issue
Post by: T 24 on Saturday, 11 March 2017, 04:37 PM
Thank you BA! That was all I needed to know, unfortunately a little bit too late, I studied all that by my self and ended up the same result!
I had exactly the same problem with my second gear. And what did I do:
-Undercut 2 and 6 gears (5 degree)
-New shift forks
-New, billet made Hayabusa shift shafts
I havent tested it yet, but maybe next week, and I really hope that all this helps, and I can use power again.
Title: Re: 2nd gear issue
Post by: grog on Saturday, 11 March 2017, 06:43 PM
excellent stuff. mine is k7, hope i never need your write up but never know. brilliant post
Title: Re: 2nd gear issue
Post by: T 24 on Sunday, 12 March 2017, 03:28 AM
Test run is done. Works great. No problem to find neutral position with undercut gears. A bit cold and slippery out there..
Title: Re: 2nd gear issue
Post by: BlackAdder on Sunday, 12 March 2017, 04:41 AM
Nice to hear that it works. My gearbox was a bit stiff on returning the pedal after upshift for some 500km but now it works as well. And I dont have any problems finding neutral either.

...that looks pretty Finnish landscape btw... :D
Title: Re: 2nd gear issue
Post by: Dan B on Friday, 22 December 2017, 11:09 AM
Hey guys.

I'm having some trouble getting from first to second gear on the 14: it's very clunky all of a sudden and sometimes gets stuck im nuetral especially under high load (i like to make the most of torque when racing sports bikes off the lights).

I've tried a few different shifting techniques to make the gear changes a bit smoother as i've been on lots of different types of bikes and there's always different tricks to getting the gear changes smooth, still does it a lot of the time.
Also get a bit of bouncing and a good clunk sometimes during gear changes if i'm shifting at a constant speed (with no load).

I'm wondering if this is related to this problem? Maybe early  (or late) signs.

The bike is my commuter and i spend a lot of time in traffic getting hot then cold and even though it has only 4,000km since the last service  (33,000km total) i've been told the oil might just need changing earlier and it might help a bit.

What do you guys think?
Title: Re: 2nd gear issue
Post by: Andre on Friday, 22 December 2017, 04:30 PM
Would first look if gearshift linkage is worn and check for clutch drag. Both can happen even at relative low mileage.

Changing engine oil would be good anyway, as well as clutch fluid.
Title: Re: 2nd gear issue
Post by: seth on Friday, 22 December 2017, 05:01 PM
the problem on early gsx1400 gearboxes was they would jump out of 2nd gear into a neutral. due to problem alreay shown earlier in this thread.
if your having problems changing gear as andre said check/change your engine oil and check your clutch operation as the slave cylinder can become sticky/stiff to use if corroded

seth
Title: Re: 2nd gear issue
Post by: gsxbarmy on Friday, 22 December 2017, 05:10 PM
Also have the gearbox sprocket cover off and check fir any build up of chain grease around the clutch push rod behind the clutch slave cylinder.

Also do you still have the original clutch line fitted? If so, this could be on the way out and fitting a braided line would definitely help as the OEM lines "balloon" (so losing pressure) as they age as the rubber goes very soft.

Early K2/K3 and some K4 models known for second gear issues, typically on those which often use all the revs in lower gears - so given you said you frequently race sports bikes from a standing start, it's possible that you have the early signs of 2nd gear failure, but do simple checks as above first and then let's take it from there.
Title: Re: 2nd gear issue
Post by: T 24 on Friday, 22 December 2017, 05:42 PM
I think it is not our "2nd gear issue"
It can be your clutch, check it carefully.
Also changing oils/oil type can help.

Are you sure you dont have such a hurry that you dont close the throttle enough?
Title: Re: 2nd gear issue
Post by: KiwiCol on Friday, 22 December 2017, 05:50 PM
Bung a quickshifter on it  :whistling:
Title: Re: 2nd gear issue
Post by: grog on Friday, 22 December 2017, 07:32 PM
or buy a gsxr 1000, sounds better suited to your needs.
Title: Re: 2nd gear issue
Post by: Dan B on Saturday, 23 December 2017, 06:19 AM
I'll do some of these checks today and see if it helps, cheers.

And grog: i'd love a gsxr1000 but i already own a worked r6 that i bring out on the weekends, the missus will only let me own so many toys.
The 14 is better on my back for the 30min each way commute to work, plus (ignoring my previous comment) it's just a great bike to ride in general, I don't wanna go backwards.
Title: Re: 2nd gear issue
Post by: Kiwifruit on Saturday, 23 December 2017, 06:13 PM
How fair is that Dan......has the missus only got two pairs of shoes ??

Ooops gotta go......"yes dear, won't be long" :worshippy:
Title: Re: 2nd gear issue
Post by: Dan B on Sunday, 24 December 2017, 01:58 PM
 :rofl2:
You win some you lose some.
Title: Re: 2nd gear issue
Post by: Cursed on Thursday, 07 June 2018, 08:04 PM
This looks helpful, although a little daunting!

I'd like to give this a go myself but the only engine i've ever stripped down is a CG125 pushrod engine. I have a haynes manual and this forum so I should have all the info.. Would you advise against it? Or is it a case of take notes and photos as I go, follow instructions and I should be ok?
Title: Re: 2nd gear issue
Post by: Hooli on Thursday, 07 June 2018, 08:27 PM
I'd try it if I needed too, but then I've been inside gearboxes & engines before. It's up to you really, do you feel confident?

At least if you take the lump out & split it to take a look & then hand it over to a workshop you've saved a lot of the labour cost getting to that point.
Title: Re: 2nd gear issue
Post by: Cursed on Thursday, 07 June 2018, 08:57 PM
Quote from: Hooli on Thursday, 07 June  2018, 08:27 PM
I'd try it if I needed too, but then I've been inside gearboxes & engines before. It's up to you really, do you feel confident?

At least if you take the lump out & split it to take a look & then hand it over to a workshop you've saved a lot of the labour cost getting to that point.

I do near enough all the work on my bikes myself, i've just never had an engine apart (aside from the CG mentioned earlier) - I suppose what you're saying re: labour is true!
Title: Re: 2nd gear issue
Post by: Mick_J on Thursday, 07 June 2018, 09:22 PM
In the 70's I had third gear bugger off on holiday from my Honda CB550f2, I have never stripped any engine before but had a go anyway.  Take it steady and follow all the instructions in the manual and you will be fine, I had my Honda back on the road will all gears working properly over the weekend.
Title: Re: 2nd gear issue
Post by: Hooli on Tuesday, 12 June 2018, 11:18 PM
The only bike gearbox I've done is my old Bonnie, much easier than the Land Rover one I did years before as no syncro etc.
Title: Re: 2nd & 5th gear issue
Post by: kquacker on Tuesday, 26 June 2018, 08:25 PM
Morning all,

I inherited a K2 with 56k miles on her. Its been laid up for the past 5 years in a heated garage and started regularly etc. Previous owner maintained and treated her well.
But in second & fifth gear she spins/slips on opening up the throttle. It doesn't jump out of gear, it just slips. I was initially thinking it was the second gear gremlin but now that it happens in fifth also, I'm not so sure.I've given her a general service as well as fitting new parts to the clutch slave cylinder with the additional seal and fresh fluid. If it was the clutch, would it not slip in other gears also?
What do you guys think ? All advice suggestions welcome.
Title: Re: 2nd gear issue
Post by: T 24 on Tuesday, 26 June 2018, 09:00 PM
Clutch problem, I think.
I had that our "traditional 2nd gear issue", and you really can hear and feel it.
The sound is like chain jumping over the front sprocket!
Title: Re: 2nd gear issue
Post by: kquacker on Friday, 29 June 2018, 02:05 AM
Quote from: T 24 on Tuesday, 26 June  2018, 09:00 PM
Clutch problem, I think.
I had that our "traditional 2nd gear issue", and you really can hear and feel it.
The sound is like chain jumping over the front sprocket!

I'm thinking clutch too given it affects 2nd & 5th gear.
Thanks for the reply, T24.


Sent from my iPhone using Tapatalk
Title: Re: 2nd gear issue
Post by: BlackAdder on Sunday, 22 July 2018, 08:51 PM
Hi. You've got it sorted allready or still under progress?

It might be the cluch basket retaining nut (the big one underneath the cluch pressure plate) coming loose - 1st gear acceleration tightens it, chagne to second it loosens and pushes the pressure plate up a bit and so on... ...known issue in aircooled suzy's. If you still havent changed all of those, pop the cluch cover open, take off the pressure plate and check the big nut - should be at 90Nm. You dont have to drain the oil either IF you lean the bike on it's left side flat. The cluch springs bolts are 10Nm and the cluch cover 11Nm. And you might want to have some sealant on hand as the cluch cover gasget most probably will brake.
Title: Re: 2nd gear issue
Post by: kquacker on Thursday, 02 August 2018, 12:13 AM
Quote from: BlackAdder on Sunday, 22 July  2018, 08:51 PM
Hi. You've got it sorted allready or still under progress?

It might be the cluch basket retaining nut (the big one underneath the cluch pressure plate) coming loose - 1st gear acceleration tightens it, chagne to second it loosens and pushes the pressure plate up a bit and so on... ...known issue in aircooled suzy's. If you still havent changed all of those, pop the cluch cover open, take off the pressure plate and check the big nut - should be at 90Nm. You dont have to drain the oil either IF you lean the bike on it's left side flat. The cluch springs bolts are 10Nm and the cluch cover 11Nm. And you might want to have some sealant on hand as the cluch cover gasget most probably will brake.
Blackadder,
Not sorted it as yet. I've been riding around the problem given all this fine weather we've been having. I'll check out that retaining nut. Appreciate the reply.
Kquacker
Title: Re: 2nd gear issue
Post by: Malarky on Wednesday, 12 September 2018, 09:02 AM
Hi Kquacker, how did you get on with this as I think I might have the same problem.
Title: Re: 2nd gear issue
Post by: Teufel on Wednesday, 12 September 2018, 11:23 AM
After fitting yoshi cams and akra system I had the same problem.
I can't remember which gears, but thought it must be power related.
I put in stronger clutch springs and it's been fine since 2012.
Springs are only a few dollars and it's an easy fix IF IT WORKS.
Good luck.
Title: Re: 2nd gear issue
Post by: kquacker on Friday, 14 September 2018, 05:57 AM
Quote from: Malarky on Wednesday, 12 September  2018, 09:02 AM
Hi Kquacker, how did you get on with this as I think I might have the same problem.
Malarkey, I haven't had time to look into it as of yet. I'm hoping to give it some attention early next month.
Title: Re: 2nd gear issue
Post by: seth on Friday, 14 September 2018, 06:29 AM
The 2nd gear problem only seamed to affect early models k2's mostly the gears were modified on later models .
:cheers:
Title: Re: 2nd & 5th gear issue
Post by: kquacker on Sunday, 10 May 2020, 04:36 AM
Quote from: kquacker on Tuesday, 26 June  2018, 08:25 PM
Morning all,

I inherited a K2 with 56k miles on her. Its been laid up for the past 5 years in a heated garage and started regularly etc. Previous owner maintained and treated her well.
But in second & fifth gear she spins/slips on opening up the throttle. It doesn't jump out of gear, it just slips. I was initially thinking it was the second gear gremlin but now that it happens in fifth also, I'm not so sure.I've given her a general service as well as fitting new parts to the clutch slave cylinder with the additional seal and fresh fluid. If it was the clutch, would it not slip in other gears also?
What do you guys think ? All advice suggestions welcome.

Well finally got round to sorting this. I found 1 bad shift fork, gears look ok. I was expecting it to be worse.
Title: Re: 2nd gear issue
Post by: seth on Sunday, 10 May 2020, 06:09 AM
Great news
Glad you found the problem and hopefully all fixed now
:cheers:
Title: Re: 2nd gear issue
Post by: kquacker on Sunday, 10 May 2020, 06:39 AM
Yes.Just got to get it all back together now. It might help anyone having similar symptoms.
Title: Re: 2nd & 5th gear issue
Post by: T 24 on Sunday, 10 May 2020, 03:14 PM
Quote from: kquacker on Sunday, 10 May  2020, 04:36 AM
Quote from: kquacker on Tuesday, 26 June  2018, 08:25 PM
Morning all,

I inherited a K2 with 56k miles on her. Its been laid up for the past 5 years in a heated garage and started regularly etc. Previous owner maintained and treated her well.
But in second & fifth gear she spins/slips on opening up the throttle. It doesn't jump out of gear, it just slips. I was initially thinking it was the second gear gremlin but now that it happens in fifth also, I'm not so sure.I've given her a general service as well as fitting new parts to the clutch slave cylinder with the additional seal and fresh fluid. If it was the clutch, would it not slip in other gears also?
What do you guys think ? All advice suggestions welcome.

Well finally got round to sorting this. I found 1 bad shift fork, gears look ok. I was expecting it to be worse.
[/quote

As you can see from your shift fork, your gears have jumped badly, and the solution is not just changing the shift fork. IMO.
Take a good look at your gear sprockets.

Those sprockets in my picks are badly damaged, but they will be ok after 4 to 5° "under cut" grinding.
Title: Re: 2nd gear issue
Post by: kquacker on Sunday, 10 May 2020, 07:15 PM
Yes I agree. The shift fork damage has to have an effect on the gears or vice versus. Although mine didn't jump out of gear, I'll err on the side of caution & get them undercut.

Good advice T24 👍
Title: Re: 2nd gear issue
Post by: GSXKING on Monday, 11 May 2020, 06:24 PM
Yep it was a problem in first models. I had mine undercut and never had an issue since.  :clapping: :clapping: :clapping:
Title: Re: 2nd gear issue
Post by: Imola on Friday, 25 March 2022, 09:51 PM
After undercutting gears do they need to be re hardened
Title: Re: 2nd gear issue
Post by: seth on Saturday, 26 March 2022, 01:01 AM
@Imola
Nice first post it might be worth heading over to the bar and say hello .
As for the 2nd gear issue
The problem only affected a few k2 bikes(Suzuki upgraded the gear on later bikes )
Do you have a problem the 2nd gear issue made it jump out of gear .
Other things that can a
Effect the gear box are wrong oil,
Sticking clutch slave cylinder and or pushrod and gear leaver being fitted in the wrong postion
If your taking the gear box out it might be easier,cheaper and better long term fitting a 2nd hand  k5 onward gearbox .
Good luck  :cheers:
Title: Re: 2nd gear issue
Post by: grog on Saturday, 26 March 2022, 07:09 PM
I once had a 2nd gear issue. Was in a hurry, pushing on. Came out of roundabout, thought i was in third, kicked her back, front wheel in air.  Guess i was in 2nd, sure wakes me up.