[Dennisgb]

So I've been trying to post for weeks and finally figured out this site does not accept posts from Ipad's or Iphones...someone should fix that.

I bought a 500 Bullet Sidecar rig with a bad engine.

The big end is gone.

I tore the engine down, bought new parts (thanks to the forum members who recommended suppliers). I bought new rockers, rod, piston and bearings from Hitchcocks. The rest of the parts came frome Ebay.

The one area of the repair that I found interesting was crankshaft or flywheel truing. There is very little real information on this for the Royal Enfield. Most of the manuals say to send it off to a qualified shop.

Having some knowledge from my Harley days, I knew the basics on how to do this. I made a V-edge fixture and set about doing this myself. I pressed the big end into the timing side flywheel being careful to align the oil holes. I torqued this side to 100 Ft. Lbs. assuming that I didn't want things to move while truing.

I put the thrust washer, rod and thrust washer on the shaft and pressed the other flywheel on to the shaft.

I then used two pieces of channel iron in my press to roughly align the flywheels.

I then torqued the other nut to 100 Ft. Lbs.

Then I set the assembly in my homemade fixture to measure runout.

https://www.flickr.com/photos/22794316@N03/44700776601/in/dateposted-public/

Intially it showed .011" on the clutch side shaft. The timing side was holding steady. This meant that the alignment was out of concentricity rather than squeezed or spread on the flywheels.

It took three times whacking it with a lead hammer to bring it to almost zero run out.

I'm not sure this is something everyone could do, but I found it fun and interesting and thought I would share it here. I should have taken more pictures, but I wasn't sure I would ever be able to post to this forum.

[cyrusb]

Good stuff going on there. Do you know anyone with a decent metal lathe? You might want to check your work on that as a final precaution.  The last few thou are usually hammered out on a fairly robust fixture (at least in my harley experience) with the pin nuts at final torque .  I have to add, between centers, a dead center in the headstock and one in the tailstock. It is the only way to see all the ways the crank can be out of true. It's a bitch of a job.

[Dennisgb]

Good stuff going on there. Do you know anyone with a decent metal lathe? You might want to check your work on that as a final precaution.  The last few thou are usually hammered out on a fairly robust fixture (at least in my harley experience) with the pin nuts at final torque .  I have to add, between centers, a dead center in the headstock and one in the tailstock. It is the only way to see all the ways the crank can be out of true. It's a bitch of a job.

Yes I do have access to a lathe. I will double check since I'm stuck right now trying to figure out how to get the old bearings out of the cases.

I made the knife edges adjustable with thumb screws so I could get as close to parallel as possible so I think my measurements are pretty good.

I did torque both nuts to 100 Ft Lbs before I adjusted the position. Initially I had the one side just snug, but had a wide (flywheels spread) reading at the journal. Once I torqued it the measurement switch to off concentric on one side.

It took 3 tries with the hammer to get to the almost zero reading. I hit it 3 times the first time and went from .011" to .006". Second time I hit it twice and it went from .006" to .002". Third time I hit it once and it went from .002" to .000" with just a tiny needle deflection that is hard to even see...well under .001"

The hammer hits were done pretty hard as I sort of remember that it takes some force to move it. I felt like I did pretty good walking it right into true.