CP gearbox inner cover differences

Singles, twins and fours.
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Pete.Silson
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CP gearbox inner cover differences

Post by Pete.Silson »

I obtained a 1948 CP gearbox for a project that had a damaged inner gear cover. I also managed to get a bare NOS inner cover. Great I thought so I carefully removed all the fittings from the damaged cover and transferred them to the new one (which took a surprisingly long time). Pleased with my work I test assembled the gearbox to check endfloat etc. and found that the mainshaft 3rd gear (27T) fouled the inner cover. The problem appears to be that the hole that the mainshaft goes through to the ball bearing is smaller on the replacement cover (1" compared with 1-1/4" in the old one) and the 27T cog is 1-1/8". Not a huge issue since I can simply enlarge the hole but, does anybody know what the repacement cover is from? W/NG maybe?
two covers 1a.jpg
I also noticed that old cover had two holes (circled) either side of the layshaft bearing.These additional holes are interesting since, my other CP gearboxes ('49 and '51) both leak grease profusely from the gearchange and kickstart shafts. Do you think that leaving these two holes undrilled would reduce this leakage?
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Re: CP gearbox inner cover differences

Post by nevhunter »

Bushed gears near that race have bigger ends, Plain bit where the teeth end. The (extra) holes you high lite allow the Oil/grease to migrate and you don't know where the level is when you're riding. I'd plug them carefully, so they don't come loose. The outer section has it's own grease IF your K/S shaft has a grease nipple and you use it now and again the shaft doesn't wear. The W/NG runs a bronze bush and NO rollers on the end of the selector drum. Easier to assemble.Totally replaces the usual steel one. If you are running a speedo drive regrease regularly especially if you ride in the wet. Nev
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