I've begun to disassemble the R90S. Started with the master cylinder. It's clean and ready to be sleeved and rebuilt. I planned to rebuild the disc brakes but ran into a problem. The bolts holding the units will not budge and it appears that someone put a wrench to one of them and damaged the bolt head. I was told by a Harley friend to use lots of heat from a torch but dont want to make the problem worse. Any ideas on how to safely remove the bolts? Many thanks in advance.
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R90S barn find update
- Thread starter ruzneb
- Start date
RPGR90s
Member
R90s bolts
The "bolts" that hold the calipers in place are actually pins or spindles. There are no threads on these pins. They're held in place by two sealing o-rings and the cap nut with spring.
You'll see a slot with a threaded center. Take one of the front axle pinch bolts off and thread it into the caliper bolt. Clamp something onto it and drive it out. Clean it up, check the two bushings that it rides in, and apply grease with new o-rings.
The "bolts" that hold the calipers in place are actually pins or spindles. There are no threads on these pins. They're held in place by two sealing o-rings and the cap nut with spring.
You'll see a slot with a threaded center. Take one of the front axle pinch bolts off and thread it into the caliper bolt. Clamp something onto it and drive it out. Clean it up, check the two bushings that it rides in, and apply grease with new o-rings.
R90S update/
The bolts are on the bottom of the forks beneath the calipers. I'll try to post pix.
The bolts are on the bottom of the forks beneath the calipers. I'll try to post pix.
R90S caliper removal
On pg 191 of the shop manual is a pix of what you've described. So the problem is trying to remove the cap nut-- that's what's locked up. Think heat will do the trick?
On pg 191 of the shop manual is a pix of what you've described. So the problem is trying to remove the cap nut-- that's what's locked up. Think heat will do the trick?
That large cap nut can be a problem. I would try a good penetrant like Aero Kroil. Get a good fitting wrench...19mm I believe...and a closed end if possible. While holding the wrench, then hit the other end of the wrench with a hammer or dead blow hammer. The shock helps to break it loose. You could heat the cap and let it cool, and hit it with the penetrant so it can wick in as it cools. Remember that it's lefty-loosey! You're looking at it from the top and be sure you're going in the loosening direction.
R90S cap nut
At least one of them(left side) has been chewed up a bit may have to use vice grip on it. Got plenty of Kroil so I'll try to remove them with a little heat. Got my fingers crossed.
At least one of them(left side) has been chewed up a bit may have to use vice grip on it. Got plenty of Kroil so I'll try to remove them with a little heat. Got my fingers crossed.
