XT600 front fork header problems
 

Hi,

i presently have a problem with steering on my 1995 XT600 and there is a hard spot when i try to steer. i have tried loosening the lock nut found under the upper fron fork header clamp and it solved the problem a bit. it is quite annoying and dangerous and can anyone help? was thinking about dismantling the whole front to check for the bearings?

I'd check the headstem bearings. On another brand bike I had they developed evenly spaced brinelling that made the front feel "ratchety" when turning from lock to lock. I'll post a photo tomorrow.

Regards Steve

Yo
 

YO Steve,

many thanks for rapid feedback

will wait for photos and looks like i will need to strip the whole front end:(

any idea why this happens? and if i better get some spare bearings and dust seals?

Kind regards

JMR

Sounds like head bearings are shot. They normally 'wear' a depression in races in the straight ahead position which results in play. This is often noticeable as a clunk when you brake and easily diagnosed if you can lift the front wheel clear of the ground and then push the fork legs front and back - you'll feel the free play at the head-stock. Also, if you turn the bars right and left you'll feel the rough bit in the middle. The tightness you feel is a bit different and may have resulted from the locknut loosening off so the races have become overtightened (have you had the bike long - could a previous owner have tried to take out the free play and overdone it?)

Wear can happen for several reasons: old age and rough roads, bad adjustment (slack) so the bearings are hammered or accelerated wear because they have been adjusted too tight. Or simply they have not been greased enough and/or water has got in and corroded them.

Yours sound shot, so expect to replace the bearings. If they are knackered it's easy enough to do apart from driving out the inner races from the frame as there's often very little of the edge of the bearing race to hit with a drift. Just make sure they come out and the new ones are driven in square.

Set the new ones up so there's no play felt with front in the air (as mentioned above) but whatever you do don't overtighten past this point. Go for a short ride ans check the adjustment again after they have settled in.

I am new on this forum and i am amazed at how quickly and precise diagnostics from the users are.

many thanks for the advice - its true that problems started happening after i travelled through heavy rain.

Just a last question: how do you grease those bearings? there dont seem to be any greasing points and from the manual it looks as if the bearings are sealed (self lubricating ones)

Many thanks

Regards

JMR

Unfortunately you can't grease them without stripping the forks off the bike.

I can't remember the precise details of the XT forks but the vast majority of bikes use the same design of two taper roller bearings topand bottom with little more than a metal dust shield on the top and bottom of the head stock to keep out the dust and water. Some designs are a little better with a rubber seal too. On a road bike this is normally enough to keep the bearings healthy for a few years but clearly the use a bike is subject to (off-road, heavy rain, jet-washing etc.) will affect the chances of getting water past the seals and onto the bearings

A good greasing will go a long way to protecting the bearings despite the inadequacy of the seals, it's just a pain to get at them.

OK JMR, here are my fuzzy photos. They are a taered roller bearing, this is the bottom. The lines in the outer race are actually impressions. There are similar impresssions on the innner race. So you can see if you tighten the headstem nut when the rollers are in the impressions, how the bars will get stiff when the rollers leave the impressions.

One of my workmates drilled and tapped the headstem portion of his frame and installed a grease fitting on his HD so he could pump the whole lot full of grease with a gun.

regards
Steve

many thanks for the info and the pics

it will surely help and i am planning to strip the whole thingy next week end - i am not very trained at this and hope wont end up with some "extra" parts lying next to the bike once i am done!!:confused1:

good idea about putting grease nipples and will see if it can be done

Many thanks
JMR