South West Bikers | Motorcycle Forum

Hello All
I've bought a yam 650 xvs that has been chopped into a bobber,
When I'm riding it for an hour or so it's fine but after a while it seems to keep revving high when I'm changing down gears to stop or slow down when the clutch is in, the only way to stop it is to stop and let the clutch out,
The bike has been standing for a few months while I passed my test,
Could it be something to do with have dirt in the carbs or the oil/fuel mixture being wrong?
Is this something I could sort out myself or should I take it to a garage?
I'm not very mechanically minded be the way
Cheers for any help
John

Hello and welcome

Before delving into the carb, check the easy bits first. Check that when you shut the throttle, the throttle cable is returning to the stop properly. Check that any linkages, etc., are able to move freely and aren't seized. If you're happy that all the external bits are working as they should, then start to look at things like making sure the throttle slides move freely and aren't sticking in the movement. Likewise things like the floats, float needles, etc., and that there isn't a load of crud in the float bowl. Blow through the jets, and make sure they're all clean and good.

If you have access to an ultrasonic cleaner they are reputed to give good results if the carbs are particularly cruddy.

Normal going on I'd say check for an air leak or lean mixture but seeing the photo of the bike on the other thread, I'd be inclined to think it's a cable/cable routing problem due to the wider bars fitted.

See if the revving' alters by turning the bars when it happens, if it does might be worth slackening off the cable slightly, if this works, look at the cable routing and/or perhapsget longer cables made up.

Where are you ?

I sorted a similar issue out on a bandit. It turned out to be a choke cable. It had been routed a different way to look neat but was fouling and not sitting off fully.

Once engine was hot it ran like crap or would over Rev in traffic.

Cheers lads, so it could be a multitude of things, reckon I'll book it in a garage,
I'm in Par billinom8

Hoops wrote:Cheers lads, so it could be a multitude of things, reckon I'll book it in a garage,
I'm in Par billinom8

I'd still check the obvious things like cable routing/oiling & linkages first - that's the sort of thing that eats time in labour bills, yet is very simple and basic to do .....