Vibration through bars

[KiwiCol]

Good on ya Bluedragon, an interesting observation & possible remedy for those with vibrations. On a GSX they'll be "Good Vibrations",   naturally.

[grog]

Thanks Bluedragon, i thought once throttle balanced,All butterflys opened together in all rev range. Guess youve taught me something. not sure how it changes but someone will tell.

[Andre]

Thanks Bluedragon, i thought once throttle balanced,All butterflys opened together in all rev range. Guess youve taught me something. not sure how it changes but someone will tell.

They do open together. All primary b-flys together and all secondary together (if they are synchronized and the TBs are mechanically ok). There is a procedure to sync the secondary as well. The primary can also be synched using another (more exact) method than commonly done.

Not all cylinders draw exactly the same volume though. One example is different valve clearance. You may set the b-flys asynchron when you balance using the common method of balancing the TBs.

[BlueDragon]

A little off topic now..

But looking at this thread

http://gsx1400owners.org/forum/index.php?topic=290.msg2450#msg2450

The width of standard GSX1400 bars are meant to be 730 (measurement A).  I'm wondering if there was a change in handlebars somewhere along the line as my standard bars measure 700.  The other measurements don't quite align to the specs on that graphic either.  My original bars have not been cut at all. 

At least the Renthal bars have been put to use though..  my son is rebuilding a GSF250 and the Renthal bars fit perfectly on it (replacing the original owners clubman bars), with just the right amount of rise that it doesn't stretch the cables etc.  Whereas the 1400 bars had too much rise and the cables were too short.

[Andre]

My K3 bar's width is 700.

[BlueDragon]

Just a quick update on this.

I checked the vacuum at higher revs and the throttle bodies were still in balance..  a little surprised at this as it is the first time I've seen this happen in a lot of years of balancing carbies and throttle bodies.

Anyway, as suggested in other parts of the forum, I checked the torque settings of the handlebar risers (standard) and the mount bolts as well as the triple clamps.  But instead of just checking, I actually loosened everything off and then re-tightened to specs.  Still no change and I had just that very slight vibration between 2500 and 3000rpm.  Mainly more noticeable as on the right side of the handlebar there was nothing, the vibes were only on the left side of the handlebar - standard bar or Renthal bar - same results.

Anyway - I then went around and checked the engine mounts with the same process of loosening everything off first and then re-tightening to specs.  What I had noticed though is that the mounts in several cases were tighter than the manual stated they should be.

For good measure, I also changed the spark plugs at the same time - even though the ones in the bike were fine when checking the colour of the plugs.

Problem now solved.  The bike is now as smooth as silk.

Just thought I would mention this as I wasn't sure how other owners have ended up with solving vibration issues.  I'm thinking it was the fact that some of the engine mounts were tightened well above specs. 

About the only vibration I get now is at idle and it is only a slight amount. As soon as revs rise - there is no vibration at all.