Vibrations??

[Scooter]

Hi all, recently purchased an AT and been using it to run along to work o a daily basis which has made a nice change from riding the scooter (people tend not to ignore me now or assume I'll move. Or just go away).

The thought did occur to me that possibly I was wasting the bike so thought I would take it for a quick spin down the A3, see how it handled at speed...see whether I panicked and tried to leap to safety. Anyhow, once I got up to about 60mph the vibrations kicked in and got were there up to 80, which is as far as I made it. The vibrations through the footpegs and handlebars were hectic and I thought it would shake itself to pieces. If I touched the tank with my knees...well...let's just say interesting sensations. I was only out for 30 mins or so but when I got back my hands and feet were all tingly and took a while to get some feeling back in them. Is this normal?? I can't imagine doing a trip at 60 with this sort of thing. Uncomfortable just doesn't cover it.

Any thoughts / advice most appreciated.

[Raven]

Remember that the AT is a geared bike; take it out of first

[GSPD750]

Chain? Worn out sprockets and chain. Adjustment req'd maybe.

[Mutley]

Hi Scooter,

Have you got engine crash bars on and, if so, are the bolts tight? This can lead to vibrations but yours sound pretty serious.

Are the wheels balanced? Are the discs warped?

Is the bash plate fastened on tightly or perhaps even touching the frame somewhere?

[Scooter]

Remember that the AT is a geared bike; take it out of first

Note to self: up for second...

Thanks for the quick replies.

I have givi crash bars which I didn't tighten overly (not wanting to strip them) and have seen some threads re the bash plate bolts not being tight enough so will crank them up a bit. Re the chain / sprockets - look OK and aren't that old but possibly could do with a slight tighten. Discs and pads fairly new too (c. 1 yr).

So. Likely suspects: 1. check bash plate / crash bar bolts 2. check wheel balancing 3. check chain tension. Sound fair?

[fatowl]

You can check if it's caused by the engine or the wheels/running gear by getting up to 80, then pulling in the clutch, and dropping engine revs. If the vibration goes away it's the engine. If it's still there, it's the wheels/chain etc.

Might help narrow it down a bit.

[Scooter]

Thanks fatowl. If it's the engine?! What fixes there??

[Whealie]

Re the chain / sprockets - look OK and aren't that old but possibly could do with a slight tighten.

Just watch yourself here. The chain does have to be quite loose to look at on an unloaded bike. Much looser than you'd imagine. Check the chain is free at every kink though.
What bike it it and what sprockets are your running? If its an RD04 and someone has put a 15 tooth on the front and either left the 46 rear or upped it, it ain't gonna like riding at 80mph.

[Scooter]

Just watch yourself here. The chain does have to be quite loose to look at on an unloaded bike. Much looser than you'd imagine. Check the chain is free at every kink though.
What bike it it and what sprockets are your running? If its an RD04 and someone has put a 15 tooth on the front and either left the 46 rear or upped it, it ain't gonna like riding at 80mph.

Really? OK, will leave it then as the chain and sprockets aren't that old and look in pretty good condition. It's an RD07 which, as far as the invoices and history I have go, is pretty much standard as it comes out the box.

[Whealie]

Really? OK, will leave it then as the chain and sprockets aren't that old and look in pretty good condition. It's an RD07 which, as far as the invoices and history I have go, is pretty much standard as it comes out the box.

Then you should not be getting such vibration. Check as the others have suggested.