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Vibrations, vibrations.... SDR 990

MrK

MrK

2014-07-16 09:43:00 UTC

Hi all,

Any of you guys have experience with vibrations elimination? My bike is SDR 990 '08 and it suffer quite bad vibrations above 6k rpm. It is not bad when ride on twisty road, coz revs are all over the dial, but highly noticeable and dreadful on long distances on motorways, when engine sits between 6-7k rpm doing 80-85mph or so constantly. After one or two hours I feel exhausted not because of long distance, but because of vibrations.
It is not on handbars only, it is whole bike vibrates. I've been trying to reduce vibration on handlebar using different types of dampers and bar ends. It is a little better, but not much.

I had recently engine rebuilt, new gaskets, valve clearance checked, throttle body balanced, etc. When I mounted engine back in to bike I was looking for some bolts tightening order guidance in repair manual, but couldn't find anything like that. As I know this may be very important to reduce vibrations, but due to lack of info I only tightened all bolts with adequate torque.

What I can do to limit vibrations level? Any suggestion welcome! Would better fuel map help with this?

Anyone here have a SDR '08 and live in West Midlands or Worcestershire and would like to meet, swap the bikes for few motorway miles to compare? I would be highly appreciate if I would know that this is not every single bike problem and it can be sorted...

ktmguy

ktmguy

2014-07-16 09:48:00 UTC

Post missing.

MrK

MrK

2014-07-16 10:07:00 UTC

Sorry I didn't mentioned, forgot about it....

My bike is modified quite a lot. I have Yoshi exhaust, DNA air filter, PC3 (map prepared on dyno, but previous owner did it, I don't mind to get it on dyno again if there is a chance to improve). Also, related to the engine itself - STM slipper clutch and Rizoma clutch cover. This reminds me, that original clutch cover had a small, disc shape damper attached inside, where Rizoma don't have such a feature, but is hard to believe that this small thing would do much difference...
Other mods are probably less important in this case.

No. 47

No. 47

2014-07-16 10:18:00 UTC

Torque spec. is in back of owners manual - M10 45Nm from memory - vibes could be caused by many things but check engine mounts first, particularly rear lower as mine unwound and fell out unnoticed.

Lack of clutch damper does not cause any perceptible increase in vibration.

May be in your part of the world - Meriden - some time soon so will let you know - mine's 90mph at 6k with 16-39 gearing.......................

MrK

MrK

2014-07-16 10:34:00 UTC

I know torque spec, all bolts torqued as per spec. What they didn't mentioned is in what order all bolts should be tightened.
All engines mounts in place for sure, I checked that several times.

From my memory - I have 16-41 gearing, therefore slightly higher revs on similar speed.
Meriden is close enough