Reply With QuoteYour primary chain may just need adjustment. It commonly causes vibes when loose. I'd try that first...
Hi all,
I've been working (slowly) through suggestions and mods to try and reduce engine surging at 2-3k rpm (details of previous thread and mods at bottom of this post)...
But I've now got reduced surging - (from highly annoying to just slightly annoying) - but I seem to have 10-20% increased engine vibration. I'm wondering what might have caused this. Any thoughts?
Mods complete:
1. Zip wired exhaust valve open
2. Cleaned + tightened ground wires
3. Added extra ground wire from coil bolt to battery -ve
4. Breather mod: 2 into 1 exiting to front of engine with no filter/catch can
5. Vacuum cleaned my air filter (looked like it had been used on farm machinery)
From the outset, the pcv/crank breather valves seem to have a lot of movement in the visible turret (is this correct?) - and my new hose/tubing is a heavier gauge than standard and I'm wondering if it's stopping the valves settling at the correct angle - or if I've a problem with the valves/fitment.
Previous post:
Surging most noticeable 2-3k rpm (though it does show less noticeably at other revs), see previous thread engine surging 2-3k rpm again
Your primary chain may just need adjustment. It commonly causes vibes when loose. I'd try that first...
While you are over there adjusting the primary chain, you probably could adjust the clutch tension bolt under the cover, there is a sequence you do with the clutch cable. It is real easy to do and after 10K miles it quieted my chatty engine. I adjusted the Primary chain with the engine hot, and the clutch with the engine cold. Not sure why I did it that way, but seems to have worked? Next time I will adjust both with engine hot, which is in another 7K miles for me. I am mechanical enough to do the maintenance and appreciate how easy and little maintenance these bikes require, but maintenance is required, just glad I can do most if not all of it.
Thanks guys - I'm slowly learning the routines - but the extra vibes weren't there before and are literally straight after the last few mods ie, breather, extra ground wire and air filter clean.
Do you think they could have caused the increase in vibration in any way?
In my one year experience with maintaining a 09 Uly, it seems like when you change something, such as an air filter, it takes the bike a little while to figure it out? Especially when I put in a new K&N air filter, there was an old K&N already on there, the first few start ups the bike idled higher, and would run like it was not warmed up and sometimes sputter. I am no expert, but to me it was like the new air filter caused it to run richer, until the fresh oil got sucked out of the fabric, and or the fuel injection Magically adjusted to compensate. The other mods, breather reroute and grounding were like butter, nothing but smoother running with those mods. If done properly these mods in my opinion are harmless, and in no way could increase vibration. My unexpert opinion is that they may have made your bike run better so that now you can now detect vibrations that may have not been noticeable while it was running rough? Good thing about this site is there are a lot of experts here that can give better advice than I can.
Thanks again TBone. - I'll try running the bike in for longer.
I also had it suggested it was cold weather.... It was just starting to frost the evening I did my test ride. Cold and hard rubber mounts not yet warmed and softened up.., !?
Rode bike again in milder weather - and increased vibes still there - so not weather related... mmmhh???
Did you ever figure out what was making your bike vibrate. I recently have had same issues. Just started one day. I ever checked my isolator and everything looks good. I am confused just add much as tough.
Nobody with this problem on this thread checked their primary chain tensioner yet? As per above, that remains my advice for the first & simplest place to start!
One other thing to check is the exhaust mounting. If the exhaust has shifted or the mounts are worn, it can translate into vibration (from what I've read and experienced).
But I would start with checking the primary.
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