Sherco 290 Shock & Linkage

[scotty97]

Took my 07 Sherco 290 out on the weekend for a couple of hours, and the rear end was make a squeaking noise when going over every little bump (sounded like my bed! ha ha), last time i was out on it, it was quite wet and bike got quite muddy.

Had a quick look when i got home and the noise seemed to be coming from the bottom of the shock or the dogbones.

When bike was up in the air on the stand (rear wheel off floor) i noticed that there was a couple of mil of vertical movement, doesnt seem to be a lot, just something i noticed. is this normal????

A few weeks previous my needle bearing packed in on the rear brake, so i made an aluminium bronze bush to replace it and it works perfect, has anyone done this mod on the dogbones????

Im hoping that the bearings just need to be repacked with grease and obviously i wont know the state on the bearings until i get them off the bike, just thought i'd ask the questions anyway.

What grease do people recommend for these bearings????

any other info or tips on this subject would be appreciated.

[scotty97]

Also does anyone know the part numbers or codes of the bearings used, cos i can order them through work direct from a manufacturer, so would only need to purchase the sleeves etc..

[tony27]

Bearings are HK1616 2RS & HK1416 2RS

There have been a few of us thinking about converting to aluminium bronze bushes for the dogbones but as far as I know none of us have done it. Care to be our guinea pig?

Best thing I've done as far as the dogbones go is to make a set of sleeves out of tool steel & have them nitrided, I've always thought the hardening of the standard sleeves to be a bit poor

Your squeak could also be a dry lower shock bearing which you don't want to have to replace because they're not cheap

[scotty97]

Just found all the part numbers for all the bearings, dogbones, swing arm and shock. hopefully order them all at the same time, so i got them there ready, just need to make some sleeves now then, anyone know the sizes for the sleeves????? i've had a quick look but none of the websites state the relevant sizes, may be a job of taking the old ones out and measuring them???

[mcman56]

I did bronze bushes with grease fittings. Check out page 3 of:

http://www.trialscentral.com/forums/index....26708&st=30

Some text is at the top and a picture further down.

Honing to a very snug fit, I was also able to get less suspension play than with the needle bearings. That said, when I have has squeaks in that area it is the spherical bearing in the bottom of the shock. (CL12?)

Edited May 17, 2010 by mcman56

[copemech]

If you can just get some lubricant to the lower shock joint it usually settles things.

Although those sleve things do seem rather soft material, the dogbone links do not seem overstressed neccessarily(like the brake), it just seems the poor seals on the expensive HK bearings let crap in and things go downhill from there, so even with fancy sleves things will go to hell if not properly cleaned and re-lubed with a good grease. The sleve things are cheap, and far too much for me to try to manufacture in the shed, no less a nitride process.

You really need to disassemble and inspect the stuff to see the condition of it all, would not worry too much with the shock at this point.

As for mcman56's experiment, I still like it and find it of interist as he states that it does indeed work without too much stiction. I myself would be inclined to start off with a bit simpler process of just a plain oilite bearing with the standard inserts and grease them well. Yet occasional maintenance may still be required, the severe corrosion of the bearings and surfaces should be greatly reduced in themselves, much like the pedal.

Oh, they all have play from new! Maybe 3-5mm at the end of the swingarm if I guess.

M2C

[scotty97]

Stripped the suspension and linkages down last night to try and get rid of the horrible squeaking noise, luckily i did it now as the bearings were all dry as hell and starting to go orange, took them all out, give them a good clean and they were in good condition. Also cleaned all the crap off the bushes, the bushes had a few little marks, but no grooves etc....

Everything once cleaned was packed with a good quality waterproof grease and re-assembled. Took the bike off the stand and bounced it a couple of times and NO SQUEAK!!!!!!!!!!!!!!!!!!!

The top and bottom shock bearings had quite a bit of grease on them, but i was wondering how you get the bushes out of the bearings. Do they just push out like all the other bushes.

After seeing how dry the bearings had gone i'l be servicing these quite often, water must get into these bearings and sit in the bearing cases.

Nevermind its all fun and im learning everytime i do something, i'l be a mechanic if i carry on at this rate!!!! ha ha

cheers for your help fellas

[tony27]

The spherical bearings in the shock push out from 1 side only, the shock has a step that the bearing pushes up to. If you plan on greasing the bearing you only need to rotate the inner in the bush until it's at right angles, removing the bearing normally damages it

[scotty97]

Cheers tony, im glad i didnt try pushing the bearings out now then

[copemech]

Stripped the suspension and linkages down last night to try and get rid of the horrible squeaking noise, luckily i did it now as the bearings were all dry as hell and starting to go orange, took them all out, give them a good clean and they were in good condition. Also cleaned all the crap off the bushes, the bushes had a few little marks, but no grooves etc....

Everything once cleaned was packed with a good quality waterproof grease and re-assembled. Took the bike off the stand and bounced it a couple of times and NO SQUEAK!!!!!!!!!!!!!!!!!!!

The top and bottom shock bearings had quite a bit of grease on them, but i was wondering how you get the bushes out of the bearings. Do they just push out like all the other bushes.

After seeing how dry the bearings had gone i'l be servicing these quite often, water must get into these bearings and sit in the bearing cases.

Nevermind its all fun and im learning everytime i do something, i'l be a mechanic if i carry on at this rate!!!! ha ha

cheers for your help fellas

Sounds as though you are doing well at it! Now you really need to do those steering head bearings as well!

[scotty97]

Repacked the steering head bearings last week, had the forks off so i thought i'd kill two birds with one stone. Ha ha.

End of my gear lever has loads of play in it, so my next job (probably tonight) is to remove it and tighten the rivot up. sometimes it feels like your changing gear and your just moving the toe piece up & down.

Copemech, forgot to say, i priced up some of those oilite bearings that you mentioned, they seem to be a lot cheaper than the needle bearings. I had a word with a mechanical engineer in work, he was surprised they used needle bearings that close to the back wheel (mud) as they are known for holding water in the casing of the bearing, he seems to think that the oilite bearingswould be ideal for dog bones etc. let me know if you end up using them and how they perform.

[manwithtool]

The montesa dogbone links or link were available from a supplier on ebay with normal bearings, sounded like a good idea to me....can't be too difficult to make up some dog bones with plain bearings (like wheel bearings maybe).