peterb Posted June 30, 2009 Report Share Posted June 30, 2009 Hi Jan, Here is a possible solution for you. It may be that you have the later type bearings while still keeping the sleeves on the crank shaft. The 05/06 bearings (can't remember the changeover year for the new main bearings) require three seals each, an O ring seal on the inner groove of the bearing, an O ring seal on the outer groove on the bearing and a specific oil seal to fit on the inside of the bearing. This seal is a specific Gas Gas seal though there is a commercially available unit that is 1mm wider and seems as though it would work - though I have not tried this myself. Note that the crankcase LHS housing has an oil drain hole that is drilled out to lead into the drain plug area, this is to allow gearbox oil to feed via capillary action from the top of the bearing and exit to the bottom and out into the gearbox area. When you fit this LHS bearing, make a mark on the crankcase with a felt pen, where the drain hole is, and the corressponding hole on the bearing. Heat up the case with a hot air gun while freezing the bearing, complete with 3 seals in the freezer. Line up the marks for the oil drain and let the bearing drop into the housing. You can leave out the sleeves with the newer type bearings but remember the 3 seals per bearing and the LHS teflon oil seal - difficult to fit squarely - best to use a drift turned up from scrap. Should be ok after that. Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
jandyb Posted June 30, 2009 Author Report Share Posted June 30, 2009 Hi Peter Seems like You just confirmed what I was thinking. Dropped by at GasGas today and brought home a set of the new type bearings and seals. It seems like a much better solution than the old type. Crank part number and case part numbers are the same. Now I am positive this will work! Only thing is the sleeves or bushings at the crank have to come off. I was thinking they didnt have to, but of course they do. Any tip how to get them off? Ahh.. one more question: Which way should the seals go into the bearing? Closed side in or the open side in? Open side in seems the most natural, but one never know... Just some food first now and Im starting on the fifth teardown. I`m getting good at this now. Last time was one hour and fifteen minutes from complete bike to engine in atoms... Wish me luck! -Jan Quote Link to comment Share on other sites More sharing options...
peterb Posted July 1, 2009 Report Share Posted July 1, 2009 Hi Jan, Good luck! The sleeves should pull off the crank shaft, if tight then try levering very gently with a fine screw driver, if still too tight then use a hot air gun to heat up the sleeve and prise off. The bearing oil seals have the spring that tensions the sealing lip facing into the pressure area (open side facing the crank case, closed side is face down into the bearing when fitting) Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
biffsgasgas Posted July 1, 2009 Report Share Posted July 1, 2009 Peter B is dead on here i think. That o ring under the sleeve has been known to do this. It gets hot and crumbled when i took mine appart to do my seals. My sleeve was very stuck to the crank shaft. I like that design. If the seal wears a groove you can just replace the sleeve rather than get a whole crank. Some one in Andora was paying attention. Go GasGas! --Biff Quote Link to comment Share on other sites More sharing options...
jandyb Posted July 1, 2009 Author Report Share Posted July 1, 2009 Report: Finally got the sleeves off. Using a visegrip and heating the sleeve and chill the crank. There should be a special tool for this? After having a break borrowing my sons 125 and playing around a bit I have now driven in the new bearings. Ensured that the drain hole LHS is open and also driven in the seals in the bearings. A little concerned that I havent got them far enough in. Are they supposed to go a little bit outside the outer bearing? About a millimeter or so? Put the crank in the freezer hoping that it will drop nicely in tomorrrow. Again I must say that this looks like a much better solution than the old bearings and seals. This cannot leak! At least not when things are new. If the bike is still smoking now I will find the deepest lake nearby and drop it in the middle! hehe... -Jan Quote Link to comment Share on other sites More sharing options...
peterb Posted July 2, 2009 Report Share Posted July 2, 2009 Hi Jan, The crank should almost be a push fit into the bearings, not so tight like an interference fit with the newer bearings. With heat on the bearing housings and the bearings in the freezer, they should just drop into position. Well, maybe the bearings do stick out a mm or so, can't say for definate - you'll find out soon enough if it is ok! Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
jandyb Posted July 2, 2009 Author Report Share Posted July 2, 2009 Hi Jan,The crank should almost be a push fit into the bearings, not so tight like an interference fit with the newer bearings. With heat on the bearing housings and the bearings in the freezer, they should just drop into position. Well, maybe the bearings do stick out a mm or so, can't say for definate - you'll find out soon enough if it is ok! Bye, PeterB. No such luck for me. Even with bearings straight from freezer and heated housing they were a pain to get in. No "drop in" here.. Even though the crank isnt that tight into the bearings at least the right hand side needs a lot of force. I didnt meen he bearings out of housing. Thats OK the outer bearing ring is about one mm inside housing, and the inner bearing ring is abou even with housing. What I meant was the seals that goes into the bearing. I am not sure I got them far enough intor the bearing. Now they are about even with the inner bearing ring. No! I dont want to find out "soon enough". This time I want to be 110% sure everything is OK before I get it together... -Jan Quote Link to comment Share on other sites More sharing options...
peterb Posted July 5, 2009 Report Share Posted July 5, 2009 Hi Jan, Yes, the bearing seals usually sit flush with the bearing outer face. A friend tried the fit of a commercially available seal that is 1mm wider than the GG unit and this does stick out from the bearing - approx 1mm - it looked as though it may have done the job but we did not try this out - too much time to lose! Happy trialing! PeterB. Quote Link to comment Share on other sites More sharing options...
jandyb Posted July 5, 2009 Author Report Share Posted July 5, 2009 Thanks I wasnt very sure that it was OK. The seals looked aukwardly "squeezed" where they sat, but as I didnt manage to get them further in and it was equal on both sides I gave it a try. Got it together on thursday evening, but as lucky as I am I managed to destroy the clutch cover gasket, and also the vater pump seal had given in after all this messing around so first there was plenty of water in the gearbox and next a pool of water contaminated gear oil under the bike... :-) Lucky the norwegian GasGas importer are only 30 km away, so friday evening I had theese parts in hand. I havent got time to try it out so much exept some rounds in my garden and a good hour in the woods yesterday. As theres still a lot of oil in the exhaust system its still dripping oil, and when it becomes hot theres also some smoke, I dont dare thinking that it is OK yet - last time it lasted for two hours - but I must say I am quite optimistic. Again I must thank the forum for all help. This time specially PeterB, but the thanks goes to everyone. I can assure You that it wont be long before my next question comes along. I have some more projects going on... Happy trailing and happy summer! -Jan Quote Link to comment Share on other sites More sharing options...
jandyb Posted July 9, 2009 Author Report Share Posted July 9, 2009 Jippeeee!! Went "trialing" with the 300 for about three hours yesterday, and all seems good now What a relief after all this struggeling.. -Jan Quote Link to comment Share on other sites More sharing options...
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