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Engine Vibrations

Well after riding Stuarts 640 supermoto and this bike back to back, the vibration had to be coming from somewhere. The rear mount was one thing I hadn't paid too uch attention to when I started the project. Stripped it down at the weekend. I dropped the back of the engine and managed to drift one of the top hat spacers out, but the other one wasn't  having it. Decided to take engine right out to get better access. Was thinking I might have to drill it out. Made a drift from a long stainless bolt and machined the head in the lathe making the lip thinner eventually, with the lip about .5mm thick I got a good contact with the end of the bush and got the bugger out. Both the spacers were about 1mm oversize on the ID so the back of the engine had about 1mm of play.  Next job is to make some new spacers and fit them, have ordered some bar stock for that. May move the oil cooler while its apart.
Recent posts

Oulton Park 16th Feb 2018

Took the bike to Oulton for a very cold trackday. Mate wanted to have a ride on his donor bike 640 supermoto. Thought It would be good for a comparison. Top temp for the day was about 7-8 deg C He is a bit braver (younger) than me, but I managed to keep up. even made a couple of passes. I think I have the edge on power and the handling is much better with the new shock, it on rails now. I can tip in exactly where I want to be and it holds a line perfectly, very stable and I didn't have a moment all day. They had to put salt down on Shell oils hairpin and delayed the start of the day for an hour to let the ice melt. A few of the faster groups had crashes braking for the chicane after shell oils and that may have been ice still in the track surface. By the time we went out it was a bit better but we still took it steady. After lunch we swapped bikes for one session but I didn't go very well on the supermoto, its just too comfortable, felt like I was out for a cruise. I need to
Few more bits done before the first outing. finally got a Tacho working. Bought a used KTM one as it seems the one I had wasn't compatible with coil feed? Also made some spacers and did some machining to fit rigid footpegs, the old ones were folding and floppy. Booked Oulton park for Friday 16th  Feb.
Been doing a bit more recently. Got the Bitubo rear shock back from Hawk racing. I bought it secondhand and had them re-build it. They are the only firm that service Bitubo. Fitted that at the weekend. Also I ordered a splitter and some mandrel bends in 50mm stainless and made a new link pipe. Fitted that too. I now have a Sealey Hydraulic bench that is just brilliant. Just a tacho to sort out now and it will be ready for the season.
Started some of the work on the winter rebuild and wanted to test another Tacho, however now thw starter spins but doesn't engage. Suspect the Sprag clutch. Ordered flywheel puller. Got it apart and garter spring knackered so replaced it and re-assembled still the same. Took t out again and on closer inspection, the cage that holds it all together is broken due to rear on one side. The tabs on the circlip are supposed to be retained on the outer ring   but these bits have worn off so circlip is not retained. Ordered new Sprag (freewheel clutch) £70 from Fowlers. Not taking chance on Chinese Ebay jobbie.

Mallory Nov 5th

The latest trip to Mallory on 5th November was a complete success. It went well all day and completed all 6 sessions. Had a couple of things to adjust during the day but nothing that was a problem. The front end was very good, could really push it into corners, (we had cold and wet and cold and dry). Only small slip was rear coming out of the hairpin. The back end shock was disappointing. It needs a decent shock with correct spring rate and both ways damping. I might add a ring to this one to give a bit more preload but something better is needed long term. The corner speed was really impressive, had the confidence to push round the outside of loads of riders round Gerrards. Little bit conservative as temp never got over 9 deg. Its fairly gentle on tyres and fuel.  Could be a a keeper for me, its light and nimble and changes direction so easily, I found I could be very precise in corner entry and hit an apex very cleanly. Few things to do in the winter;- May need a sprag clutch at