High thought I'd post this to see if any of you technical wizards can offer any probible insight to the gear selection issues hampering the progress of 'team Spesh racing' into club racing folk law. I had gear selection issues at donny when going down the box from 6/5 to 4 then 3rd at high revs and quickly. Causing no engagement of gears at all and then a grounching sound from the box. Also some jumping out of gear when reving in 3rd/4th.
Clutch seems to be working ok, and having stripped out the clutch and gear selector assembly for inspection, I found the clutch plates ok,(apart from a little heat discolouration of the metal plates, due to high rev racing starts I suppose). But the gear selector had some wear on one edge. So this was replaced and then all refitted with new oil.
Clutch was adjusted and with the engine running and rear wheel up in the air I went up and down the box a few times. All ok, no issues. So off we went to Mallory for general testing. I managed 1 1/2 laps before i gave up. No change in the problem its still there.
So before I remove the engine and strip off the sump to have a good look inside is there anything I'm overlooking? Also please remember this engine/box has led a hard life, racing, trackdays and then racing again.
I suspect it could be one or more of the following Selector drum worn or either a worn selector fork or bent selector fork.
Theres no excessive wear indication in the oil or material present on the magnetic sump plug. So i offer this one out for info.
Not stripped yet. But having visited a couple of mechanics today its been decided its either a selector fork or the drum. So I'm going to source a good used engine. Put it in the bike, test and then aim for the next available round. Or a guest race at another club meeting.
Al i you give hanks racing a call he uses a guy who sources low mileage motors for racing at club leval roy has used him for some time. if you need a number text me or pm
engine sourced and collected today from a car breakers in Halesowen. So before I fit any advice on prepping for running. Not sure when it was last run but apart from a rocker box cover its complete. New oil and filter is of course on the list but what else? cheers Spesh. We might make Cadwell next weekend after all :-)
PLUGS OUT turn over by hand then electric drill with socket turn over check oil light goes out and no strange nosies I say use drill so you dont burn out starter if you can spin the motor over for a good few mins you can put carb clener though carbs and down plug holes . I have got a good compresstion tester if you need it I would do this before putting new oil etc in
Yeah good advice about the drill. I was going to put some oil down the bores when I turn over by hand, just in case its a little dry. No carbs though as fuel injected. But will use the original throttle body's anyway. Then new oil before I try and turn over on a drill ;-)
Now you have two complete engines, it seems a good opportunity to have one full race ready unit as a spare. A luxury I know, but really handy for a quick change of engines.
Just put cheap oil in as you will be cleaning out all the crud and muck from the pistonrings seals and cams. you could just put cooking oil in as you will not be running the engine just washing out the muck and lubing as you go. get some petrol injetor cleaner down the barrels and leave to soke overnight to work on the rings
Engine is in & turns over ok, just need to fit the radiator, exhaust & fuel tank.
However, we now need to get a new gear activator rod as it got broke when the bike 'fell' off the stand!!
Also Spesh decided that it would be a good idea to help hold the engine up on his knee & has now done something to his knee!!
All mechanicals and electricals fitted and tested. Once the tank had been refitted and I put some fuel in it the engine started first touch of the starter. so i must be doing something right for once. Run for 10 mins to prove everything was ok, ran sweet. now just the gear linkage to repair and bingo, ready for a run out :-)
Gear selector has been fixed. i'm gonna take it to mallory on weds for testing. Fingers crossed all will be ok. next stop cadwell for the racing this weekend :-)
Hi just to put an update on. I've finally got to have a good look at the gearbox today. Found some wear on one side of the LH selector fork. Also happens to be the one that moves the gear along the spline when going down from 5th to 4th. So this looks like the culprit. So the decision to be taken is to split the casing and replace both gearbox shafts with some used ones. Or just replace the selector fork? I'm in the mood to change all the bits and then I know it'll be ok. Its a pain to do but what the hell I've a few weeks to complete before the next race meeting. ;-)
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