Six spoke wheels

I'd borrowed the hollow three spoke Brembo wheels from my Daytona, pending a posh polish and paint job on the original six solid spoke SNW Trophy wheels. Meanwhile, Tim decided he had no use for his six spokers so I thought I'd make use of them (cheers Tim) as a way of returning Streaky his wheels. First off, ditch the 20 year old rubber tubeless valves. For a few pounds, it just isn't worth trusting these critical components. I've seen the front tyre of a bike blow out on a motorway. Not pretty.

Tim's wheels were a bit tired but otherwise in decent condition. I decided to give them a simple tidy up with some steel coloured wheel paint I had for years. Literally. I went for a steel colour because I thought it would pick up the graphite stripe on the Trophy bodywork, rather than the aluminium colour these wheels came in.

After a good scrub with a nylon pad, degreaser and CIF, I could see the paint on the rims was very thin and flaking. So a went over the edges with wet and dry. Also, I treated the inner surface of the rims where they had suffered from tyre irons in the past. 

Tyre iron groove ...

... treated to a foam block and wet and dry ...

... until all is smooth again.

I had some grey primer so treated the wheels to a coat of that to start with.

Unfortunately, there was still some flaky paint around the bare ally on the rim and it didn't take very well. So more rubbing back, more primer - still not great but as I was determined not to agonise over the finish, I went on to the wheel paint.

Not bad ... at a distance

Rubbing back Simoniz steel colour wheel paint as it reacts again

Well, more reaction followed, more rubbing back, more wheel paint. I think they are pretty good now.

I installed a new 160/60ZR18 Avon Storm 2 on the rear wheel ... 

... and then noticed how the inner faces of the swingarm had suffered last winter. So more rubbing back - with steel wool this time - but special metals primer this time. Marvellous. Why didn't I use it on the wheels? No idea other than this time I wasn't thinking about a quick job. I was thinking of a sound one.



As a consequence, the paint took beautifully and no futher rubbing back was required so it was actually quicker anyway. When will I ever learn.

Good as new

With the rear wheel reinstalled, I can see that the rear of the bike sits higher now. Tim discovered that there is a difference in the length of the rear shock absorber for bikes with an 18 inch rear wheel and the later 17 inch rear wheel. That figures, with the difference in stance of my bike, back on a wheel it was originally spec'd for.

Better stance with 18 inch rear wheel and original shocker

I have not yet finished the front wheel but Ruby Trophy 12 is blasting around Somerset and Wiltshire again. Soo smoooth on the new chain and new rear tyre.

Ah,  Summer time

Pitted fork repair, Sprint Manufacturing 20% uprated springs, and front wheel refit

With the forks removed, I could see how much pitting was present on the stanchions - a lot, as it happens, although each individual pit was pretty small, maybe up to 1mm across.

I decided to try filling them with Chemical Metal epoxy paste on the grounds that, well, it just might work. If not, I'll get them reground and hard chromed. So I degreased them with cellulose thinners and dug as much of the dirt out of the pits as I could with a pin, wiping as i went. Then I mixed up the Chemical Metal a bit at a time and covered the affected areas. It goes off very quickly (about 5 mins) so I had to repeat the process lots of times. 

After leaving it to cure completely overnight, I trimmed back the excess filler with a sharp blade and rubbed the stanchions down with 800 grade wet and dry paper. The finish was smooth and reasonable. I've no idea how robust it will be. 

I'd decided to fit some 20% stiffer replacement fork springs from Sprint Manufacturing. I carefully measured lengths as I went. First, the difference between fully compressed and fully extended is about 145mm. Second, the standard spacer is 110mm. 

The springs I removed were 470mm in length (the shorter, darker spring in the picture below). I would say the 'standard springs', which I believe them to be, but who knows whether a previous owner changed them. The Spring Manufacturing springs were about 490mm in length. I could have cut the spacer down accordingly (to 90mm) but decided I would treat it as an additional 20mm preload to start with and then shorten if required later on. This meant being very careful in compressing the springs to refit the top nut but they went together well.

I decided to try comparing the spring rates. No pics I'm afraid but I did this by placing an old kitchen scales upside down on each of the springs and then compressing them for 1cm. I was surprised to find that the Sprint springs were about 6kg per cm whereas the ones I removed were 6.5kg per cm. In other words, harder. So maybe they aren't the originals. However, the Sprint springs have two pitches  whereas the springs I removed were evenly wound along their entire length. The manual indicates that the originals should be twin rate. I decided I'd try to see what the rate of the Sprint springs are when the close-wound section binds. I did this by clamping the spring in my workmate just above the close-wound section and repeating the scales trick. This time, it showed a rate of 7kg per cm, so about 17% stiffer by my imprecise measurements - close enough to Sprint's claim for me to believe all is in order.

 Forks reassembled, I decided to fit a pair of stone guards. The clamp just above the dust seals. Hopefully, they'll help to keep the Chemical Metal repair functional for a little while at least.

I decided to pull the forks through the yokes slightly more than standard because the stiffer springs would make the bike ride slightly higher than normal, marginally slowing the steering geometry. Again, it's an experiment. The fact that I now know the difference between full extension and compression means I can adjust the down some more as long as I leave at least 145mm between the bottom yoke and fork seals.

I found that the front wheel axel was rusted internally. There is a plastic bung on the left hand end that had been damaged, allowing water ingress. So I cleaned it up with a drill and thin wire brush, primed and painted it before coating the bung in waxoil and refitting. I also gave the front axel nut a birthday.

 I like polishing. The fork top nuts and speedo gearbox gave me a chance to break out the Solvol and bling it up :-)

 Plenty of LM grease on the axel and the wheel is back in place. The axel can be held still with a tommy bar through the left hand end whilst the nut is pinched up. There was zero clearance between the fork legs and the wheel spacer (left) and speedo gearbox (right) so it was a performance getting the wheel in place. I managed it in the end by slackening the fork clamp bolts in the lower yoke and slightly twisting the sliders.

For torquing the axel up, it is necessary to tighten two clamp bolts in the left-hand fork leg so the axel doesn't rotate. The two clamp bolts in the right-hand leg can then be torqued too.

 Handlebars and clocks loose fitted, starting to look like a bike again.

Trophy 1200 Rear Wheel

A previous owner had painted the wheels. I really liked the idea of having red centers with silver edges for the wheels. Unfortunately, the paint was lifting in places because it seems not to have adhered terribly well to the original silver paint. After I'd given them a good scrub down, with gunk, then Jif cream cleaner, then lots of clear water, I felt I could get some good results with a rattle can. 

I found Halfords do enamel paint in two shades of red, one of which was a good match for the bike's Lancaster Red. I'm thinking of it as a temporary measure, pending getting them powder coated some time later on.

I'm keen to get riding so I'm starting to make some small compromises now, thinking I can rectify them after using the bike for a while. I freshened up the silver with a brush, steady hand and Smoothrite. To get an even finish, I put the wheel up on axel stands. That way, I could slowly rotate it on its spindle and rest my hand on the stand whilst applying the paint. I think the results are pretty good considering.

Right-hand side of the hub: disc carrier. There are six threaded holes on the right-hand side of the wheel for the chromed allen-headed bolts that retain the rear disc. I lightly smeared lithium grease around the edges of them to stop the disc from sticking to the paint. I then used non-permanent thread lock on the thread of the bolts to keep them in place and copper grease under the heads to prevent them from seizing. I had found a build up of dirt and rust in these special bolts which made them difficult to remove. Also, the rust had started lifting the chrome where the finish had presumably been damaged in previous tightening. So I put blobs of grease in the bolt heads and banged in plastic caps to prevent corrosion from building up in them in the future.  

Grease around the disc bolt holes to stop the disc
from sticking to the new paint ...

... and thread lock to hold the bolts firm after torquing them up. 

Plastic caps to prevent corrosion from building up in the bolt holes.

Left-hand side of the hub: cush drive

Installing rubber 'cush drive' blocks

Installing a greased spacer into the
sprocket carrier.  

 The left-hand side of the wheel hub contains a housing for the sprocket carrier. The housing has five alloy vanes which are driven by five larger vanes in the sprocket carrier via rubber 'cush drive' blocks. The rubber blocks serve as a drive-line shock absorber. I coated the vanes and O-ring joint with rubber grease.


A rubber O-ring sits in a machined groove around the wheel bearing so I put rubber grease around it to help keep dirt and dust out. It helped me to ease the sprocket carrier into the hub as well because it is a fairly tight fit. I'm very pleased with the finish I managed to obtain on the sprocket carrier - very satisfying indeed. I'm hopeful it will be a permanent (whatever that means on a motorcycle) whereas the wheel paint is more of a stop gap measure.

Installing the sprocket carrier to the rear wheel hub. 

I decided to fit a 42 tooth rear sprocket. There are plenty of options, courtesy of the modular nature of the range. I'm looking forward to a relaxed, torque-laden feel to the ride and figure this will be conducive to wafting along at low revs when I want to.  Copper grease on the studs and some more heavy duty torque wrench action (85NM), and all is as it should be.

There is a small alloy spacer that fits into a rubber seal just outboard of the left-hand wheel bearing. The action of the rubber seal rotating around this spacer tends to wear a groove in it. Plenty of grease should help. Job done.