hi all is there any way of retarding the throttle on my 290 as my son has just started to use it and he`s a bit throttle happy and gets in some right pickles and is gonna hurt himself badly if something isn`t done about shortly. would sizing up the front sprocket and down sizing the back really make that much difference. thoughts on this most welcome.

Best thing I ever did was retard the ignition on my Sherco. Made the bike much smoother in the power delivery and the bike gripped a lot better as well. It also stopped the kickback that happened sometimes on starting as well.

white tube fast black tube slow

Someone had one of them spacer blocks that come with the homogolation kit, it limits the travel

My son rides for MRS Sherco now and we have carried out several mods to engine etc to smooth it out, but you do need the black (twist grip part) slow action throttle for sure.

AS,

Do you know if any have experimented with the cylender base spacers listed in the '07 catalogue?

Are you referring to a 2.9?

John B., a little change makes a big difference, hu?

Oh, Big Ian, going to the 9 tooth front will slow the bike a lot, and is cheap to do! Very recommendable!

Will not prevent the power from dragging you around though! What age is he?

Edited December 27, 200619 yr by copemech

AS,

Do you know if any have experimented with the cylinder base spacers listed in the '07 catalogue?

Are you referring to a 2.9?

No, i'am talking about a 125, i hav'nt changed base gasket.

The standard 125 is very sharp at the bottom end, but our 125 is now very soft low down, but with more than enough power to take me (12 stone) around a decent club trial.

It would be worth playing with more base gaskets on the 290 as this should smooth out the power.

My son rides for MRS Sherco now and we have carried out several mods to engine etc

Shouldn't this be front page youth news Alan?

My son rides for MRS Sherco now and we have carried out several mods to engine etc

Shouldn't this be front page youth news Alan?

Maybe i don't realy know, AG IOW is the only one i know who knows how to put stuff on the front page.

I thought most people new this anyway. He may post something soon as i know he has some important other news around the corner.

AS,

Info on the cyl spacer would be helpful as the part illustration is only for that purpose.

I have ordered some parts but yet to recieve them. Logic dictates that with the minimal thickness of the spacers, another gasket would be required to sandwich it properly and seal things off which adds to the total thickness increase.

Not too sure if anyone knows (short of Paxau) about this at this point, and I cannot reach him! Hell, I cannot even get MRS to answer an e-mail either for that matter!

I must admit I am a bit surprised at the need for softening of the 1.25, thought they would need as much as possible. They are quite good, much stronger than my '02 bike for the wife, which is Much better than the '06 GG i last rode!

Parts information on Sherco website lists them as gaskets of different thickness's. Correct me if I am wrong but it does not say spacers, I would think you would remove the original gasket and replace it with one of the new thicker gaskets. There are three extra gaskets of different thickness's listed as well as the original.

Not too sure if anyone knows (short of Paxau) about this at this point, and I cannot reach him! Hell, I cannot even get MRS to answer an e-mail either for that matter!

MRS dont answer emails

As for the base gaskets, it will make a lot of difference, a club member had one on his gasser and it was a lot smoother but needed a bit more throttle for the big stuff.

copemech

Like John said there not spacers just gaskets of different thicknesses, I'm fairly sure the new base gaskets are there so the factory can get the squish set up to the perfect hieght as there will allway be a variance in the sizes of the various parts. My cabestany model had a extra base gasket 0.1mm thick and the squish was set at 0.55mm. I think the standard squish is around 0.6mm but don't quote me on that.

By the way the new base gaskets will not fit the 06 bikes or any of the older bikes as the centre cases and the barrel where changed for the cabestany and these where caried forward on to the 07 model.

Hope this helps

Chris

Chris,

Close inspection suggests you may be correct in that there may indeed be two gaskets stacked on this thing already! For fine tuning as you said, I suppose!

However, the primary gasket, M 681 appears to be a carryover in the parts book.

Now I am really confused!

I don't think the Sherco parts manuals and parts numbers are foolproof.

They list the same number (M245) for early and recent 290 pistons, but I understand the '06 and '07 models do not have a cut out in inlet the skirt, whereas the earlier ones do.

Now the fitting of a later piston in an earlier engine may well result in interesting porting (and lack of power) changes!