New bike - clutch sometimes won't disengage

[southbound]

2011 xc250r
Fresh 5-30 oil
Clutch lever adjuster screwed all the way in (btw, the lever still has lots of play before it tensions up)
Third ride, ever.

Sometimes the clutch will disengage, and sometimes it will not. This is a problem in technical sections where I need to stop the drive.

Thanks.

 

[Fred1956]

Clutch lever adjuster screwed all the way in (btw, the lever still has lots of play before it tensions up)

This is a big no-no, the adjuster screw too tight will cause the M/cylinder to not fully stroke the slave as it can't properly 'reload' with fluid. Try backing it out to a gap between screw & piston then work gently in. Could have air in it from day 1 but unlikely.

 

[GGEvo]

I had a similar problem with my '10 EC300. It was a faulty seal in the master cylinder. Clutch would engage for a few seconds then disengage. Fixed under warranty.

 

[twowheels]

2011 xc250r
Third ride, ever.

Sometimes the clutch will disengage, and sometimes it will not. This is a problem in technical sections where I need to stop the drive.

Thanks.

I had the same thing happen on a 250 XC earlier in the year, and experienced the onset of it on a 300 Six Days with 5 hours on Friday. A couple customers of mine also experienced the same problem on their 2011s.

A master cylinder rebuild kit will most likely solve the problem, but only because you end up cleaning out the plunger bore and master cylinder when you install it anyway. My new 300 Six Days had a couple pieces of machining debris the size of a broken pencil tip obstructing one of the ports from the MC to the plunger bore, and a small piece of swarf stuck to the diaphragm. I cleaned everything out, forced some fresh mineral oil up from the bottom, worked out the tiny bubbles, and buttoned it back up better than new.

Try this first and see if it doesn't solve your problem before you try chasing down one of the last remaining AJP rebuild kits. Here's a hint though - Trials Parts USA bought up all of the remaining inventory they could get their hands on when the company went out.

 

[gasgasman]

Put a Magura master cylinder on the bike.
AJP was having quality control issues, that's why Gas Gas went to the Magura m/c.

I put a Magura on my 2011 bike. It is 100% bolt on.
The engagement point is "wider" than the AJP.

 

[southbound]

What's my source for a Magura master cylinder?

 

[gasgasman]

I got mine from DennisKirk.com
$130
If you want the choke lever on the master cylinder, you will have to order one for a 4 stroke with the hot start.

 

[blitz11]

Hi Girard,

Do you have a part number/cylinder bore diameter? Are there choices?

Is the Magura only mineral oil? i am thinking if the M/C on the 2002 goes bad, a swap might be in order.

thanks.

craig

 

[gasgasman]

This is the one I have.
https://www.denniskirk.com/magura/10-5-mm-master-cylinder.p571733.prd/571733.sku
There are different piston sizes. I figured the bigger piston will have a easier lever pull.

 

[blitz11]

Actually, bigger piston means tougher lever pull, but more volume moved for a given amount of lever travel. It's good to know that the 10.5 lever moves enough oil to disengage the clutch.

Thanks for the information.

craig