[Captain Bert]

Pretech engineering have closed and unable to contact them. My query is the caliper has 2 halves held together by 5 bolts. Recently my caliper locked up and upon investigation the bottom 2 piston seals had seized up. I had to completely dismantle the caliper to get the pistons out.
I have ordered and received new seal kit, BUT I need to know the torque wrench settings for the bolts!.
Does anyone have any details on these? Any details would be much appreciated, as guessing could lead to problems. Mike from TTP sells some spares but didn't know the settings and quoted the owners are retired and uncontactable.
😕🥺🙄😬

 

[snake89]

Pretech engineering have closed and unable to contact them. My query is the caliper has 2 halves held together by 5 bolts. Recently my caliper locked up and upon investigation the bottom 2 piston seals had seized up. I had to completely dismantle the caliper to get the pistons out.
I have ordered and received new seal kit, BUT I need to know the torque wrench settings for the bolts!.
Does anyone have any details on these? Any details would be much appreciated, as guessing could lead to problems. Mike from TTP sells some spares but didn't know the settings and quoted the owners are retired and uncontactable.
😕🥺🙄😬

Man just snug them up then give it just a little extra. They will be fine.

 

[Captain Bert]

Man just snug them up then give it just a little extra. They will be fine.

The Calipers are a machined alluminium alloy , too easy to strip the bolt holes. Anyway I have torqued them up to 25Nm

 

[[email protected]]

What's the bolt size - 6mm? I wouldn't go much more than 25nm/18-19ft lbs at that size, and possibly even less. The M6 bolts on the engine casing and cylinder head are 10nm and are the closest thing I could think of that deal with heat and pressure/stress issues. Would thread lock help keep them in-place, or would the caliper heat defeat the purpose? Loctite 2422 is high-temp and still only medium strength, so you could still work on the caliper from time to time. Give it a shot and take some progressively longer and faster rides, let things cool, and see if anything loosened up.

 

[Captain Bert]

The bolts are 4 x M8 and have used loctite on the threads as there was evidence of thread lock when I removed them. Any way I have passed that stage and having put new a Disc rotor/caliper seals/master cylinder piston kit/brake pads in and spent a lot of time bleeding air out of the system (god that is a slow process) I am yet to get out on the road and test the brake.
The original problem was the caliper seals on 2 pistons had sheared seal pieces between the piston & bore causing the pads to lock on the rotor at 100kph and lead to brake vapor lock. When stopped smoke was pouring off the disc and you couldn't move the bike. Lucking I was on a club ride and tailend charlie had a spanner to bleed off the brake fluid, I then had to limp home rear brake only. Scoured the disc with deep gouges . . . so complete brake rebuild.
Wife said . . you better sell it! YES time for a T120 (but I'll probably keep the T100 as well)