4strokertwin Posted January 28, 2010 Share Posted January 28, 2010 Hi guys, help is needed on 2 matters please. I have been restoring my 1978 xs250, of which was last on the road in 94, I have been collecting parts, gen Yamaha where possible with new and nos. I have stripped, cleaned, polish and painted some items over the last 3 years. I am about to rebuild the motor with all new bearing shells etc. what oil should I use, the same as I would when the motor is up and running, semi syn 20w50 or something like Wynn's super charge oil, the motor my stand for 6 months before its up and running, (well I hope it does any way). Also, Can anyone recommend anyone in the UK, where I can have parts passivated olive drab. Thank in anticipation graham Link to comment Share on other sites More sharing options...
Speedshop Posted January 28, 2010 Share Posted January 28, 2010 my advise would be if the shells are Ok, leave well alone. Minor scuffs or slight marks in a shell bearing doesn't mean it needs new. Have you plasi-gauged them and found what the clearences are? Replacing shells on Japanese bike engines where the tolerences are very fine is more likely to cause more problems then not. leave well alone if the tolerenes are within the service limits. I don't ever remember the XS250/400s requiring 20/50. 10/40 was what we used to use. If you don't use the lighter oil they can destroy the cylinder head. 20/50 takes too long to get up to the head, to the plain bearing that the cam runs in. I remember the 250 was worse then the 400 and having a couple of destroyed heads that were put down to wrong oil. 10/40 can take 20-30seconds to get up there from cold start and 20/50 a minute or so depending on the temp! All that time the cam runs with no lube (or what is left on the bearing surface i should say. My 400 had a slight pick up on the cam bearing in the head, but i used a bearing scraper on it to clean it up. It ran like that for another 25,000 miles when i had the bike and was going strong for a couple of years after I sold it. Never use synthetic oil on a newly rebuilt engine. Use basic mineral for the running in procedure then switch if you feel the expense warrants it. To be honest though on such a lowely tuned engine you won't get your money's worth from synthetic, just use normal and change it early if you want the best protection. i doubt its ever had a drop of synthetic in it before now - and its still here today! And leave the engine to last, its not good to leave it standing too long newly rebuilt, the new seals can dry out and be torn when you finally start the engine and clutches can weld themselves up. Use moly grease and 10/40 mineral oil on all the plain bearings, splash the 10/40 over all the steel parts in the gearbox/clutch case and wipe the bores with the 10/40 too. You don't need 'special' or 'super' lubes. Well only if you belive all the lubricant company's BS. Look in the ads in Classic Bike or classic mechanics for platers Link to comment Share on other sites More sharing options...
Moderator drewpy Posted January 28, 2010 Moderator Share Posted January 28, 2010 i've used 10/40 before and the motor didn't like it. that's why i went with 20/50 semi synth. i've used the bike for 3 years now and there's no wear in the bore or camshaft. yamaha recommend 20/40 but that's impossible to get over here in blighty. your right about using mineral oil in a newly built engine. i used duckams and thrashed it for 40 miles to bed in the bores etc. then used the 20/50, tried 10/40 and back to 20/50! when i rebuilt my bike i used assembly oil which is like treacle and sticks to surfaces. i used this because it was a while till i was able to fire it up and it gave it the best possible protection. i never used drab olive as i bought new bolts which were already done plus stainless throughout the rest of the bike. drewps Link to comment Share on other sites More sharing options...
4strokertwin Posted January 29, 2010 Author Share Posted January 29, 2010 SPEEDSHOP-Re oil, I think drewpy answered that one for me, as for the crank & con-rod shells. I have cleaned and polished the bottom crank case, cleaned & resprayed the top and side covers, had the cylinders bead/vapour cleaned, and the head cleaned and valves reground, so I think I would be daft not to put new in after a total nut and bolt restoration of the bike, and after spending in excess of 1.5K. The idea was to rebuild the minimum of the motor, not the clutch and oil pump etc. to lay the motor on its side and then lower the frame over, fix in place rather than try to put in a rolling chassis, with the likely hood of damaging the p/coat on the frame, I would prefer this way, but as said above, afraid of damaging the frame. What do others think of this way of rebuilding the bike, has anyone rebuild this way with no problems. I have found 1 coater for olive drab finish, but asked for others for there personal experiences, as I have had some bright zinc coating done, and was not happy with it. So recommendation I was after. I have just read on another forum that this firm I used is crap even for there chroming and service. GRAHAM Link to comment Share on other sites More sharing options...
Moderator drewpy Posted January 29, 2010 Moderator Share Posted January 29, 2010 The idea was to rebuild the minimum of the motor, not the clutch and oil pump etc. to lay the motor on its side and then lower the frame over, fix in place rather than try to put in a rolling chassis, with the likely hood of damaging the p/coat on the frame, I would prefer this way, but as said above, afraid of damaging the frame. What do others think of this way of rebuilding the bike, has anyone rebuild this way with no problems. I put some masking tape with sponge on the frame rails, engines go in/out from right hand side I have found 1 coater for olive drab finish, but asked for others for there personal experiences, as I have had some bright zinc coating done, and was not happy with it. So recommendation I was after. I have just read on another forum that this firm I used is crap even for there chroming and service. GRAHAM i think the rd aircooled had a supplier but did a search and couldn't find it! why don't you use a casswel kit and do it yourself? drewps Link to comment Share on other sites More sharing options...
4strokertwin Posted January 29, 2010 Author Share Posted January 29, 2010 I put some masking tape with sponge on the frame rails, engines go in/out from right hand side i think the rd aircooled had a supplier but did a search and couldn't find it! why don't you use a casswel kit and do it yourself? drewps As for the kit, £150+ basic £49.00 if I know what I know now, I would have done. the first lot of zinc cost me £110. have still more to do, plus the olive drab The only firm I have found that still do olive drab is Collins Chemical Blacking, surrey. they gestimate £50. for 31 items, food pegs and washers,clips & screws on air hoses. I had thought whether to spray sat black(pj1)to save money. (but will it look OK, not authentic??) Link to comment Share on other sites More sharing options...
Moderator drewpy Posted January 29, 2010 Moderator Share Posted January 29, 2010 As for the kit, £150+ basic £49.00 if I know what I know now, I would have done. the first lot of zinc cost me £110. have still more to do, plus the olive drab zincing cost £100!! i think mine cost a £5 about 20 items!! ( 3 years ago though at RS chrome) The only firm I have found that still do olive drab is Collins Chemical Blacking, surrey. they gestimate £50. for 31 items, food pegs and washers,clips & screws on air hoses. I had thought whether to spray sat black(pj1)to save money. (but will it look OK, not authentic??) they've been around for a while and advertise in CMM but I hav'nt used them. PJ1 is good, but not that good. i did look into painting stuff , but the vendors said for longevity get 'em plated! Link to comment Share on other sites More sharing options...
4strokertwin Posted January 30, 2010 Author Share Posted January 30, 2010 Thanks drewpy, I've never came across that firm b4, ( goggle search) I will email or phone them to check if they still do it. I am going to rebuild the motor last, and pad out the frame. is it right side as you look at bike or sit on. Yep 110 for zincing, and some have to b redone, they didn't even undo the nuts from bolts so the ends and insides where not coated. graham emailed the above, and they have got back 2 me, the cost is £60 + vat. Inc return p&p Link to comment Share on other sites More sharing options...
Moderator drewpy Posted January 30, 2010 Moderator Share Posted January 30, 2010 Thanks drewpy, I've never came across that firm b4, ( goggle search) I will email or phone them to check if they still do it. I am going to rebuild the motor last, and pad out the frame. is it right side as you look at bike or sit on. always sit on Yep 110 for zincing, and some have to b redone, they didn't even undo the nuts from bolts so the ends and insides where not coated. graham emailed the above, and they have got back 2 me, the cost is £60 + vat. Inc return p&p it was 3 years ago and they are local to me, must have put them in another job! like all other stuff, prep is the key. Link to comment Share on other sites More sharing options...
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