Forza 300 shaking at front when pulling away.

[Deleted User 407]

I have had the Forza 300 nearly two years now and had the steering bearing changed under warranty around October time when i had slight vibrations through the handlebars.Since then i have had a vibration when pulling away from slow speeds, could this be the belt as i also had the bike serviced around July when i thought they might have told me if the belt needed changing.Last week I had the tyres changed thinking it may have been causing the vibration as the old tyres where nearly gone but the vibration is still there when pulling away.
Anyone any ideas?

[MrGrumpy]

A vibration when pulling away could well be a CVT issue - my old Yamaha engined Aprilia Leonardo was terrible for this - but I seem to remember feeling the vibes through the rear rather than the bars. If it is this, it probably isn't the belt itself, but maybe more to do with the clutch mechanism - either worn or just full of grime and dirt. Hopefully, a real expert will be along in a moment to advise you!

[Q-Ball]

I have had the Forza 300 nearly two years now and had the steering bearing changed under warranty around October time when i had slight vibrations through the handlebars.Since then i have had a vibration when pulling away from slow speeds, could this be the belt as i also had the bike serviced around July when i thought they might have told me if the belt needed changing.Last week I had the tyres changed thinking it may have been causing the vibration as the old tyres where nearly gone but the vibration is still there when pulling away.
Anyone any ideas?

Get the bike on the center stand get someone set on the pillion seat and get the front wheel in the air. Grab the front forks and give them a firm wobble,also turn lock to lock for any roughness in the bearings. Any head bearing issues should show with this quick check.
Could possibly be a CVT issue as mentioned, remember vibrations can resonate through the whole bike,so something at the rear could well be felt through the bars.
I doubt it's an unbalanced tyre issue if its noticeable while pulling off as the tyre won't be spinning quick enough.
Is there only vibration when accelerating and not when slowing or rolling on from say 30-40?
Can you replicate it with the bike on its center stand!
Personally my money is on a CVT vibration,head bearings would always be noticeable even more so under braking.
For how easy it is,I'd pull the CVT cover and look for signs of belt contact on the cover,also start it up and have a visual look while it's running. There always seems to be some flapping about of belts while there running but not anything excessive.
You should of seen my timing belt flap around on my old Rotax CCM,it was scary,good job it was covered or you would swear it was about to jump a tooth.

[Q-Ball]

A vibration when pulling away could well be a CVT issue - my old Yamaha engined Aprilia Leonardo was terrible for this - but I seem to remember feeling the vibes through the rear rather than the bars. If it is this, it probably isn't the belt itself, but maybe more to do with the clutch mechanism - either worn or just full of grime and dirt. Hopefully, a real expert will be along in a moment to advise you!

Think your very possibly in right about the CVT issue. Can't be anything that serious, scooter CVT systems are possibly one of the simplest transmissions ever designed,a quick clean to get rid of dust,de glaze the clutch and bell and they seem happy to keep going.

[StephenC]

Mine is getting for 3 yrs old and for a while it has had a judder when pulling away - it's almost certainly dust build-up in the clutch housing. If you can, open it up and have a clean out or ask for it to be done when next serviced.

[Data]

As others are indicating, this is certain to be a clutch issue. Judder moving off on dry clutch cvt's just indicates, as Stephen is saying, a build up of clutch & belt dust in the clutch drum. The clutch shoes also become glazed & will need careful deglazing with a flat sanding block & 100 grit Emery paper. Important to keep the shoes very flat & not alter the radius of the shoes as you do this. You don't want to remove much material. Clean & sand the inner clutch drum surfaces lightly too. It'll be fine after this.

The only other thing that can cause this is oil or grease contaminating the shoes. Of course check the front fork bearings but I doubt that's the problem. Usually they don't behave like that if bearings are loose. Good luck!

[Deleted User 407]

Thanks for the replies.Should this have been looked at when I had a yearly service done about 300 miles ago? If so that dealer is going to get a phone call.

[MrGrumpy]

You'd expect them to have a look - there again, this is by far the muckiest time of year, with roads covered in wet salt, mud and all other sorts of grime.

[Data]

There usually isn't any mention of servicing the clutch eg: cleaning it out, deglazing etc on any dealer service. You have to tell them there's an issue & they'll sort it. Mostly the clutches don't need much attention. If it needs attention often, it's usually due to owners not using enough power on take off. That can cause the clutch to slip more generating extra dust which causes judder at times.

Generally I'd do a clutch service every 15,000 miles on the Burgman 400's. Mostly that would keep them ok if the owner was treating it right. It coincided with belt and roller changes. So not really any extra cost for owners. My GTS300 clutch gets done every 8,000 miles when I change the belt & rollers. If it's done separately on any scooter it'll cost you another hours labour depending what bike.

[StephenC]

Funny you should say about not using much power to pull away - mine seems to have gotten worse since the spread of 20mph zones on many of London's major roads.