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Ajp 2-Piston Caliper Leak? Need Help -

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I just bled the front brake on a 1995 JT35 Contact. It seemed fine on the ride, but upon close inspection a few days after riding there is some brake fluid that appears to seep from the center line in-between the 2 caliper halves, Tightening the mounting bolts seemed to stop seepage from the partition line. I don't feel any change at the lever.

Is this normal or do I have to rebuild the caliper? or should I just replace the caliper with a 4-piston unit?

I spoke to Jim Snell, who feels that the 4-piston AJP doesn't provide much more braking capability, but is not as rigid. In fact he still uses the 2-piston caliper on his JTX despite access to aftermarket parts.

The original disc guard had washers in it. If you are missing the guard or washers the bolt could of bottomed out. When the lever is pulled it flexes and leaks. The original front brake worked fine, unless you are very talented you would not gain a thing.

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The original disc guard had washers in it. If you are missing the guard or washers the bolt could of bottomed out. When the lever is pulled it flexes and leaks. The original front brake worked fine, unless you are very talented you would not gain a thing.

I have the disc guard and washers in place, so I believe the 2 caliper mounting bolt tension is correct.

Based on your response, what I am observing must be normal for AJP 2-piston calipers.

The one I opened up years ago had an o-ring on the mating face, between the two halves?

its possible the seal inbetween the 2 halves is failing undoe the two halfs and get it matched up with a bearing seal stockist or poss universal seal selection box

yep need new O-ring in the middle where the fluid passes between the halves. Just make sure new O-ring is right size and will be compatible with brake fluid.

yep need new O-ring in the middle where the fluid passes between the halves. Just make sure new O-ring is right size and will be compatible with brake fluid.

My guess also, a new o-ring will help. What we did with the early single pucks was to lap the center mating surfaces (240 grit on glass works, figure "8" motion

with even pressure and use a little water), which seemed to greatly reduce the caliper halves flexing in use.

Jon

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