So on a 2015 pro can anybody tell me what the proper spec is? I've heard from two different dealers one 85ft lbs and the other 65. Big difference. Thank you guys
Primary clutch torque
- Thread starter moly may
- Start date
Indy Dan says 70 FT LBS. But he also has a full page set of instructions on how to install and torque a clutch properly. In a nut shell (IIRC) it is; If you have a Fugi Type 2 crank you must lap the clutch to the crank. (The "Type 2" Fuji cranks *0262* should be lapped to fit as they were Not "Nuts On" when they machined the angle of the taper). The Mapes cranks fit well without lapping. Both the crank stub, the clutch taper, and your hands need to be clean and dry. Install the clutch on the crank stub and torque cold to 70 FT LBS. Heat cycle it without riding it or having a belt on it. Torque to 70 FT LBS again. Do that 2-3 more times before putting a belt on or subjecting it to a load. Install belt and subject it to a light load, torque to 70 FT LBS. For the first few rides check the torque and if it takes torque keep torquing it to 70 FT LBS until it does not take torque any more.
If this procedure is followed your clutch should not split in two. FWIW
A lot of people over torque it once and run it. IMO that is why the clutch splits at the end of the crank snout.
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Good post LH.
15's have the "Fuji" cranks...
BTW... Factory manual give a spec of 80 ft. lbs., repeat after running the sled.
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15's have the "Fuji" cranks...
BTW... Factory manual give a spec of 80 ft. lbs., repeat after running the sled.
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What does lap the clutch to the crank mean.
X
xc6rider
Well-known member
70 ft/lbs. run it a little, torque it again. Repeat this process until it quits taking 70 ft/lbs.
Once it quits taking 70 ft/lbs torque, it's where it needs to be.
Above, is what I received in instructions last from Indy Dan, and what I have followed for the last 5 years... It usually takes 3-4 torque sequences after the initial 70 ft/lbs. And that's basically putting around the parking lot in short distances, from what I've found.
Once it quits taking 70 ft/lbs torque, it's where it needs to be.
Above, is what I received in instructions last from Indy Dan, and what I have followed for the last 5 years... It usually takes 3-4 torque sequences after the initial 70 ft/lbs. And that's basically putting around the parking lot in short distances, from what I've found.
From Wikipedia
"Lapping is a machining process, in which two surfaces are rubbed together with an abrasive between them, by hand movement or using a machine."
This is my method;
Apply some (valve) lapping compound to the crank taper, gently mate the clutch to the crank, and with light steady pressure rotate the clutch on the crank taper (the crank stays stationary) about 10-15 degrees back and forth a dozen or so times.
***Be sure and clean all the lapping compound from the tapers.***
If you want to check your work, and you should, get some Prussian Blue and put a very light smear (you do not want any thickness, just a thin smear to colorize it) across the bottom of the crank snout, mate the clutch to the crank snout, but let the clutch rest on the top of the crank snout and gently side it up until it seats. carefully remove the clutch and look inside to see how much and where the Prussian blue transferred. If it does not have a full length consistent blue line across it, you have more lapping to do. Repeat until you are happy with the Prussian Blue verification of mating surfaces.
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I updated my original post as I found the Paperwork and I was Incorrect
I updated my original post because I had the wrong torque value and the wrong crank manufacture called out to be lapped (my memory is not what it used to be). The quote below is the correct info as is my (now updated) original post. Others who quoted me originally will be the incorrect info. Maybe MH or the poster who quoted me can fix it.
I updated my original post because I had the wrong torque value and the wrong crank manufacture called out to be lapped (my memory is not what it used to be). The quote below is the correct info as is my (now updated) original post. Others who quoted me originally will be the incorrect info. Maybe MH or the poster who quoted me can fix it.
