gaz Posted March 4, 2009 Report Share Posted March 4, 2009 (edited) Alright chaps, The main bearing has gone on my 08 rev3 250. I rang lampkins and they have said that the bearing is a special. Has anyone got the bearing reference number and can i get one off the shelf from a bearing supplier? I seem to remember that I could on my 04 sherco. I know this sounds tight but I thought Edited March 4, 2009 by gaz Quote Link to comment Share on other sites More sharing options...
fivemeister Posted March 4, 2009 Report Share Posted March 4, 2009 (edited) I know this sounds tight but I thought Edited March 4, 2009 by Fivemeister Quote Link to comment Share on other sites More sharing options...
chubs Posted March 5, 2009 Report Share Posted March 5, 2009 agreed,get your wallet out ya tight git Quote Link to comment Share on other sites More sharing options...
betabegood Posted March 5, 2009 Report Share Posted March 5, 2009 Hi, I have just got some mains for my 04 model, they are all the same i believe. Got them from a local supplier, the only thing that's different from the norm is they are double metal shielded code zz or 2z. Ill get the size today and post up the numbers tonight. They were Quote Link to comment Share on other sites More sharing options...
gasgasian Posted March 5, 2009 Report Share Posted March 5, 2009 Don't mean to sound funny, but if its a 08 bike its not something that you should have to sort out. Think your bike should last a bit longer, if you have suggested to JL that you will sort it thats what they like to hear!! Regards, Ian Quote Link to comment Share on other sites More sharing options...
wayne_weedon Posted March 5, 2009 Report Share Posted March 5, 2009 I have just got some mains for my 04 model, they are all the same i believe. Got them from a local supplier, the only thing that's different from the norm is they are double metal shielded code zz or 2z. Ill get the size today and post up the numbers tonight. They were Quote Link to comment Share on other sites More sharing options...
plunker1 Posted March 5, 2009 Report Share Posted March 5, 2009 These ceramic main bearings made a big difference in my 125 Sherco's ability to rev. vary smoothly to the moon!! and they have lasted over a year now. http://www.ceramicbearings.net/products.htm Quote Link to comment Share on other sites More sharing options...
betabegood Posted March 5, 2009 Report Share Posted March 5, 2009 Hi, If they are the same as an 04 then you need some 6206 zz c3 (c3 for incresased tolerance to allow for heat expansion??) Mine were less than half price of genuine ones for a good quality bearing. I also asked why they are metal shield type because surely you want the oil to get in and the supplier said they are shielded not sealed and when you look closely you can see small slots round the edge of the shield to allow oil in. There is an oil way on each casing half directing oil to the bearing and some space behind the crank seal when bearing is fitted to allow oil up behind the seals. Also would be worth checking if they can also supply the crank seals @ Quote Link to comment Share on other sites More sharing options...
wayne_weedon Posted March 5, 2009 Report Share Posted March 5, 2009 I also asked why they are metal shield type because surely you want the oil to get in and the supplier said they are shielded not sealed and when you look closely you can see small slots round the edge of the shield to allow oil in. Yes I know the difference between Z and RS bearing types I specify and purchase bearings regularly I still don't agree with the shields. Never seen a two stroke with factory fitted shielded mains and I've rebuilt more than I could remember how many. Not rebuilt a modern Beta though. C3 Bearings have increased radial clearance. This allows them to be fitted to tighter housings without binding the race. It's also wise to specify a decent branded bearing for mains. None of the Far Eastern stuff unless it's Japanese should even be entertained. Get friendly with a proper bearing stockist and the prices is so close anyway. 75% + discounts in the trade is commonplace. Wayne.... Quote Link to comment Share on other sites More sharing options...
betabegood Posted March 5, 2009 Report Share Posted March 5, 2009 Well i'm no bearing expert but like I said I also questioned why they were shielded just as you said. Just stumbled upon what the codes mean while searching for the new bearings on the web as anyone would. I also thought it would be best to get as much oil to them as possible and was going for the regular type as they seem cheaper. Who knows maybee my bike has been apart before I owned it and incorrect ones were fitted at that time but they look original. Cases don't seem to have been apart before. Perhaps it may have been wise for me to ask lampkins if they would read me the code on one of their oe bearings and then I could have gone from there. I'm just assuming they are correct. All i've done is replaced them with what came out, and if they do me another 5 years then I will be happy. And thats 4 more years than the ones in Gaz's bike by the sounds of it. I'm not going to get into some sort of debate because I don't know enough on the subject. He asked for the size and that's 6206. Anyway good luck Gaz whatever type you decide to fit hope you get it sorted Quote Link to comment Share on other sites More sharing options...
wayne_weedon Posted March 5, 2009 Report Share Posted March 5, 2009 (edited) No debate/argument intended Just seems real odd based on past experiences to me. Just to clarify the C3 stuff and why in a engine. It DOES have a temperature relation but more for the cases. A good design bottom end will have tighter (Smaller) bearing housings, this is to ensure as the engine gets hot the bearing do not spin in their housing. BUT this would not be good for a standard radial clearance bearing as it would pinch up and run tight. So C3's have the same dimensions (Bore/Outer race diameters) BUT have more internal clearance which closes up on fitting to the tight housing. Hope that helps... Wayne... Edited March 5, 2009 by wayne_weedon Quote Link to comment Share on other sites More sharing options...
gaz Posted March 5, 2009 Author Report Share Posted March 5, 2009 Don't mean to sound funny, but if its a 08 bike its not something that you should have to sort out. Think your bike should last a bit longer Thats exactly what i thought!!!! I spoke to JL's and they stated that because of the item involved they could not tell if its a manufacturing defect or rider caused (i.e. dunked in water). So I said fair enough..... I had spoke to a guy who had an 08 beta, and exactly the same had happened to him after a couple of months! Out of interest on the bearings themselves, why would they be double sealed, 'zz' ??? as apposed to just 'z'. There is a BSL supplier that the company I work for has an account with so I'd imagine NSK or SKF would be good enough for this application? Quote Link to comment Share on other sites More sharing options...
betabegood Posted March 6, 2009 Report Share Posted March 6, 2009 Hello, I would go out and check that the shield ones are the correct type before you buy them as this has got me doubting that I have bought the correct ones. I can't be 100% sure that the ones that came out of my bike were the originals. Also my bike is an 04 270 so you may also want to check they are the same part number on the beta site When you get the cases apart you will see what I mean about the space behind the crank seal and bearing, one possible thing I thought is perhaps the fuel oil mixture builds up in here to some sort of level behind the seal and then trickles slowly through the bearing to lubricate it and the shields stop it from passing through too quickly???? Just an idea though don't know for certain. I would not expect them to have gone after 1 year though. My old thing looks like it has had 5 years of hard abuse on what I think are the originals. Would they not do you a deal like they supply parts you pay labour or something like that? Quote Link to comment Share on other sites More sharing options...
betarick Posted March 7, 2009 Report Share Posted March 7, 2009 08 rev3 have had a set dodgy crank bearings fit from factory is what i heard! my brothers bearings failed doing the scott and also heard that a couple of john lampkins riders retired aswell doing the scott with the same problem? bearings need to be open race to get oil to them or they will fail again! Quote Link to comment Share on other sites More sharing options...
gaz Posted March 8, 2009 Author Report Share Posted March 8, 2009 I heard about a the factory fitting some cheaper crank bearings, but wasn't sure if that was just hear say. Also enquired at BSL and a set of SKF's, which are a good brand, are Quote Link to comment Share on other sites More sharing options...
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