Use calipers and measure ID of steerer tube top & bottom every 30-degrees and verify hole is round. It’s possible coating may have variable thickness and hole is not perfectly round.

Also measure OD of bearing cups and verify they are round.

If you find that both frame and bearing cups are ovalised, mark their major & minor diameters so that you can line up major axis of cups with major axis of frame when installing.

A little bit of gear oil on cups when installing helps.

I’ve always used long bolt and stack of big washers. Try to get hole through washers/plate to fit snug on bolt. This provides centering effect. I also place one smaller washer underneath that’s smaller than ID of cup to keep entire stack centered. Go gently with bolt, just 1/4-turn at time and inspect alignment. If cups start to get crooked, tap down high spots gently with hammer on the plates.

Be sure you adjust bearing-preload after couple hundred miles. Tapered roller bearings have narrower adjustment range than *****. Just 1/8th turn between turns between too loose vs. too tight.

 

Many thanks, I'll do this in the morning when I have some light but two points the skew is not in the same direction each time and the frame was blanked off before coating so there is no coating inside the steering tube.

Would this suggest that it would be the bearings themselves that are oval?

It might take until next year to get washers - I cannot think of anywhere round here that would sell them that size so it will have to be a well known on-line auction site :-)

Once again, thanks for the advice.

 

You’re welcome!

Bearing races are most likely round. Measure them to be sure.

Measure head steerer tube. It may have gotten ovalized from previous crash. I’ve fixed these by cutting wooden-blocks with curve, then squeezed in vise.

You want both of these to be round within +/- 0.05mm (0.1mm total variation).

Flat plates can work if they’re thick enough to not bend. Just make sure bolt and plates are perfectly centered in head tube. I prefer at least 1/2” bolts. Squeeze slowly and correct crookedness before squeezing any more. Maybe you know someone in bicycle shop that can lend you headset press tools?



I’ve also used these thick plates from Home Depot before.

https://www.homedepot.com/p/Simpson-...3HDG/100506792

 

I've checked the bearings and they are circular to the tolerance my callipers will measure to.

I've measured the steering tube and, again, I cannot detect any ovality but the upper tube has a very small area of roughness near the base of the seat - I'll take that down with wet and dry.

I've been out and bought some sheet steel and some 10mm repair washers, these are 47mm od so big enough for the upper bearing but not the lower. The steel is only 1mm so I propose to use a repair washer up top and washer, steel, washer clamped by two nuts underneath - does this sound a workable solution?

Whatever, nothing is likely to happen now until after Boxing Day :-)

 

The process is proceeding but my ignorance is getting in the way.

The bike is now, effectively, back together and I'm testing the electrics. My problem is that, when I turn on the headlight, it comes on for about 5 seconds and then goes off again.

I've, taken the nose cone off again to inspect what is there as the wiring diagram showed nothing that could produce such and effect and found that the bike has had a Xenon conversion fitted.

I know nothing about Xenon headlights.

It is possible that the bulb has been knocked during the rebuild (almost certain) but is there anything about a Xenon setup that could cause this?

 

Well the rebuild is complete and I'm happy with the result except for the fairings which do not fit as well as they did (which was not good in the first place). The problem appears to be with the front fairing being too far forward and too high.

Here's a photo of how the frame turned out (fairing removed to rivet the VIN back onto the frame) which gives me the chance to show off the frame :-)




I've done about 250 miles since the rebuild and she's running really well. Fifty miles since I had the suspension set up which has made a massive improvement to the handling. Dropped the forks by 1mm and a couple of clicks less rebound, a tad more compression damping on the rear shock and increase the rebound damping and the bike turns in so much better and feels a lot more stable. I cannot recommend MTS Suspension Services enough for anyone in the East Midlands area - Matt is thorough and very professional.

 

Woohoo!! Turned out awesome! Good job!

 

Well done, great job

 

She's looking well buddy that frame came out great I've gotta go all through this with mine yet and being honest, I'm not looking forward to it "at all, all I've done so far is take off the seat the tank remove the battery box and the butchered hacked away at undertray tail light hanger along with the regulator and already have had bolts snap and one so rusted I've butchered the head so I'm going to have to drill it out this does "not bode well for the rest of it methinks. Are you going to be putting the rest of the fairings on her?

 

Yep, she’s back together and 50 miles further down the road (just to make sure there are no rattles you understand). Two outstanding jobs now, sorting (and maybe replacing) the fairings and replacing the front disk rotors that are a bit ridged - jobs for another week :-)

Luckily my seized bolts were on the chain guard so they stayed and the hugger came out as one - best of luck with yours, you’ll enjoy doing it and get a buzz when you finish it.