Vibrations on 750J - advice please

[MikeH1A]

My old girl has recently had a bit of a tune up, which included fettling the front brakes. Now when I ride her she gets noticeable vibrations on the left side. When I'm out on the highway, I can feel steady tingling and vibrations through the left hand grip/bar but nothing in the right grip. (Feels a bit like riding the Kawasaki ). This seems apparent at speeds above 65mph or so. Today I took my beloved for a blast and she mentioned afterwards that she felt quite strong vibrations through the left rear footpeg but nothing really in the right one.

Any thoughts what might be causing the bike to vibrate down only one side when the revs and speed are getting up there? Thanks

[Alan H]

Does the vibration get worse as the engine revs rise or with speed? When the vibration starts to get bad pull the clutch and drop the revs.
If it's speed and not revs, check chain/sprockets/wheels. Don't overtighten chain.
Left footpeg might suggest chain area.

[MikeH1A]

Thanks for the prompt reply ... and from the other side of the world. Am I up late or are you up early ?

As I think about it, I would say it is more in relation to the speed rising. Seems to only be when out on the open road which is 60mph (and above ). It is definitely only on the left side. I had thought it was only in the front as I could feel it through the left bar (nothing through the right at all) but today, my wife certainly noticed it in the left footpeg. She said it felt like her foot was going to bounce off.

I shall check the chain as a starting point. Thanks

[Alan H]

7.13 am originally, so not too early. Then went to a local-ish bike show and spent too much on tools and stuff, as you do!

Make sure the gearbox oil is OK, then check everything along the rear left, so sprockets, chain, wheel alignment, wheel bearings etc.
Have a look at the tyre too, it may be going a bit 'blocky' for want of a better phrase. I recently had one on a van that went strange and it felt and sounded like a wheel bearing was on its way out after about 50mph or so.
If you get to the vibro speed then pull the clutch and hit the kill switch that will tell you if it's engine /clutch drive related or further towards the clutch driven, gearbox or back wheel area. If you do a gearbox oil change make sure there's no metallic bits in the drained oil or stuck to the magnet if you have one on the drain plug.

Failing that, if it doesn't happen when your dearly beloved (or wife) isn't on the back, then she may need a full service including a new left knee joint.

[Coyote]

I would suspect tires or wheel balance. Check your rear sprocket for wear and make sure the chain is not trying to 'climb' on the sprocket

[Craig380]

Maybe also check the mounting bolt and rubber mounting bush for the exhaust hanger on the left side -- if it's loose, it'll vibrate, and if the bush is perished, it'll vibrate ...

[MikeH1A]

Thank you guys. Plenty for me to check next weekend. Appreciate your thoughts

[re5rotary]

Don't go 65mph and then you will be fine besides it illegal you know! Cant say I noticed it when I rode it. When did it start, after the tune up or was it there before?

[MikeH1A]

Hey T, What are you doing lurking on forums - you can't have run out of jobs in that big garage of yours surely? I told you this place is for bikes that have pistons LOL. 65 is nothing on a Waterbus, I had her up to 85 yesterday going to Little River Nah, it's a new thing and only on the left side. Noticed it again heading towards and over Gebbies yesterday

[Suzukidave]

Check the rear exhaust pipe mounting , if when tightened down the pipes hangers are touching the frame it will allow the engine vibs to be transferred to the frame . the hangers have to float in the rubber mount , use small washers to make sure the pipe hangers do not touch the frame .

[re5rotary]

Hi mate well if you cant find anything bring it over and we can have a look. Hows our oil consumption looking? T