Newbie Initiation Tricks-Swingarm Removal

[Patton]

Title sez it all.
Got two bikes down to the frames. The 8mm collar bolt has been removed and the collar has been spread open.

On one frame the 12mm hex head is close to spinning in its slot. I stopped with the torque prior to buggering up the female side of the hex/slot. I moved on to frame two.

On the second frame the 12mm bolt "unscrews" and as it does the threaded side of the bolt pushes the frame out, yet the bolt will not come out. So I screwed it in, and out, and in, and I had had enough and went ahead and stripped it.

Do I resort to the saws-all and cut the bolt(s)? Suggestions...

Bad initiation trick, ya'll should be ashamed.

RP

[454MRW]

I have used a small bottle jack before to spread the frame apart slightly to get a Sawzall blade in between the threaded swingarm sleeve threaded nut on each side of the swingarm and the inside of the frame rail to avoid cutting into the frame rail or threaded nuts. If you go slow and are careful you may get lucky. Once you get the arm out, you can unthread those nuts and possibly get the rusted in sleeve and bolt out of the swingarm with a hydraulic press. The bearing cages usually have to be almost cut in 2 carefully with a die grinder, then split with a carefully applied chisel and pried out. The bearing sleeve (tube) that the swingarm bolt goes through and that turns in the needle bearing cages is not available, but you can usually find a swingarm for sale on eBay with a usable tube, or I may have (1) that, although will not be in new condition, would be able to get you by. You can get new needle bearings. [email protected] Good luck. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1978 KTM 250'S
1975 Can Am 175 TNT 250 conversion
1976-78 125-400 RM's & 79 PE250 Suzuki & 2012 DR650
2007 CR125R Honda
1977 MC250 Maico

[Cal Alexander]

Does your Penton have the rubber isolated bushings in the Swing Arm or is it the later needle bearing version? If its the rubber isolated bushings I cut the swingarm bolt on both sides. Once you have the swing arm off you can punch out the bushings with a bearing press. Hit the swing arm and bushings with some Mapp Gas heat before you press them out. Al B. has new swing arm bushings in stock.

75 250 MC
74 Jackpiner
72-73 Six Day
72 Berkshire
70 Six Day

[454MRW]

I believe his earlier post was a 72 175 and a 74 125. Mike

Michael R. Winter
I enjoy rebuilding and appreciating Pentons!
1974 250 HS Pentons-1978 KTM 250'S
1975 Can Am 175 TNT 250 conversion
1976-78 125-400 RM's & 79 PE250 Suzuki & 2012 DR650
2007 CR125R Honda
1977 MC250 Maico

[ALB]

For the swing arms with the needle bearings, I have a couple of the axle tubes still in stock. I also have plenty of the bushings and the needle bearings in stock.

The swing arm bolt is a common overlooked maintenance issue. The bolt should be removed at least once a year to clean and grease it so that it can be easily removed. If the bike is being raced or ridden on a weekly basis (especially if riding through water) then the bolt should be removed, cleaned, and greased at least once per month.

Since this maintenance was not performed 20+ years ago you almost always have to cut the bolt in order to remove the swingarm for a restoration project. Whatever you do, be careful not to strip out the 12mm x 1.5 nut welded into the frame. Stripping the nut will result in more work in cutting out the old nut and welding in a new one.

Alan Buehner

[Patton]

Thanks, everyone. The bottle jack will be in use tonight to spread the frame(s).

Really bad trick for you'se guys to do to us newbies. Will order new bolts and bushings from Alan soon.

Again, thanks for your support.

Robert Patton