konvikts6 Posted July 26, 2015 Share Posted July 26, 2015 Hello all, just a quick one. me and a friend have both completely stripped and rebuilt our entire engine on our xs250's. rebuild has been strict and torqued appropriately whilst ensuring that all parts still turn freely.i dry fitted the crank case at the kickstart side and re assembled the kickstart shaft correctly. and its at this point both of us found that when engaging the kickstart lever we could not get it to turn the engine and feels like its locked.my friend even rebuilt the whole engine again in case he missed something but we are still stuck at this same problem.now i was thinking maybe its because the engine is still dry apart from the lubrication used when refitting all the parts however im reluctant to fill then engine up with oil and drain it again as i didnt want to fill with oil until it was actually on the bike as this model requires that you remove the oil filter to place the engine back into the frame.Thanks from both of us for any help in advance! Link to comment Share on other sites More sharing options...
Moderator drewpy Posted July 26, 2015 Moderator Share Posted July 26, 2015 is the side cover fitted?I always have issues getting the kick stop and gears to mesh when putting in the kick shaft.Its usually trial and error for me and I've rebuilt 3 engines 1 Link to comment Share on other sites More sharing options...
konvikts6 Posted July 26, 2015 Author Share Posted July 26, 2015 Thanks drewpy!so basically im turning the shaft clockwise so the stop is as far clockwise from the stop position as possible then im inserting it and turing the spring clockwise with some grips then hooking it onto the spring holding bit. then putting the cover on and im not sure whether it doesn't engage or its just too stiff. am i doing something wrong or should i just try and put it in again and try and make sure the gears mesh if thats the problem? Link to comment Share on other sites More sharing options...
Moderator drewpy Posted July 26, 2015 Moderator Share Posted July 26, 2015 hard to tell via text, sounds about right what you say.maybe try and do it again, you don't need to drain out the oil, keep the bike on its side stand and the oil will drain to the left. (thats why I start the bike upright so the oil pump gets some oil to pump)just don't try and kick over without the cover on as it will snap the crankcase bearing in the gearbox and will scrap the cases. Link to comment Share on other sites More sharing options...
konvikts6 Posted July 27, 2015 Author Share Posted July 27, 2015 ok thanks drewpy! and ye ye thats why i didnt want to force it as someone must have done that with my bike with the past and ive just had to strip down and weld the casing and machine it! Link to comment Share on other sites More sharing options...
Moderator drewpy Posted July 27, 2015 Moderator Share Posted July 27, 2015 ok thanks drewpy! and ye ye thats why i didnt want to force it as someone must have done that with my bike with the past and ive just had to strip down and weld the casing and machine it! ouch! may be try it with the clutch in, it won't kick over the bike but just spin the clutch basket. just in case the top was not timed properly Link to comment Share on other sites More sharing options...
Waddy92 Posted July 29, 2015 Share Posted July 29, 2015 Hello, I am said friend in question. I too am suffering severe emotional trauma with this frigin kickstart!As Kon said, I built the entire engine up only to find that when I went to push down on the kickstarter it locked completely solid. I thought, "Oh sh1te, I've done the timing wrong", but nope. I could turn the engine over by hand on the crankshaft as many times as I want. I gets a little bit stiffer when the two valves are depressed at the same time, but apart from that pretty smooth.so I took the engine to pieces again, as I thought that there has to be something fundamentally wrong with the gearbox. Took it all to pieces, checked it all, compared it to another gear box that I have, and it is exactly as per diagram. Put her all back together again, although I haven't torqued everything down fully until I know it works, just nipped it up.So at this point I knew that it wasn't a bottom end problem, the issues only start when the whole engine has to turn over. So it was a case of the old process of elimination. Firstly I removed the rocker cover, so that the valves were no longer engaging, but the cam shaft was. GET THIS! It works. So I can freely turn the engine over with the kickstarter. The kickstart mechanism turns the gearbox, which in turn rotates the clutch basket, which turns the crankshaft, and rotates the cam shaft. I can do it by hand, virtually no difficultly in turning the engine over. BUT! Once I put the rocker cover on, i.e the valve springs are engaging with the camshaft, it locks completely solid. I can hang off it. It's not stiff, its locked.So the only think that I can think is happening is that as soon as a bit of pressure is applied back through the engine by the valve springs, something somewhere is pushed out of alignment, or disengages, or locks. ONLY when the rocker cover is put back on. Again, I can turn the engine on the crankshaft, but not with the kickstarter.Is there some kind of fundamental requirement for perfection on the kickstart mech. It seems a pretty simple and rudimentary design. How can it not be working? Is it lack of oil, is it spring pressure, do I need to kick the sh1t out of it?! WHAT IS HAPPENING?!!! Link to comment Share on other sites More sharing options...
Moderator drewpy Posted July 29, 2015 Moderator Share Posted July 29, 2015 have you double checked valve timing? it can be easily 180' out Link to comment Share on other sites More sharing options...
Waddy92 Posted July 29, 2015 Share Posted July 29, 2015 (edited) On the end of the CAMshaft the little pip is pointing up, when the LT mark is lined up. When I turn the crankshaft the engine turns over absolutely fine, there is no compression as I have the spark plugs out. If its 180 degrees out, will the valves still miss the pistons? Unless of course the magneto has been put on 180degrees out? So that the 'LT' mark is wrong. is that possible? And is it right that part way through the cycle, two valve springs are compressed simultaneously? No, I think that the magnet can only be in one position.... must be a kickstart mech issue. Edited July 29, 2015 by Waddy92 missed a bit Link to comment Share on other sites More sharing options...
Moderator drewpy Posted July 29, 2015 Moderator Share Posted July 29, 2015 did you try to pushjovert the kickstart with the clutch engaged so it eliminates the valve train as I suggested earlier? Link to comment Share on other sites More sharing options...
Waddy92 Posted July 31, 2015 Share Posted July 31, 2015 not tried with the clutch in yet. Is it possible because the engine has no oil? Does that make a big difference? Link to comment Share on other sites More sharing options...
slice Posted July 31, 2015 Share Posted July 31, 2015 Not as long as you don't go mad about it, just gently turn it over for f**k sake don't start it !!!! Link to comment Share on other sites More sharing options...
Waddy92 Posted August 4, 2015 Share Posted August 4, 2015 I almost bought a new engine yesterday for £100. A runner, just to I could do a bit of dismantling and see what the difference was between that and mine. However, being a tight sod I bought a kickstart mechanism instead for £15. So I'll try fitting that and see if it makes any difference. The only thing I can think of is that with the extra grunt required to turn over a fully timed engine, the mech is becoming dislodged, and that's why its jamming. Without the rocker cover on, I can kick it over, and depress the kickstarter by hand. With the rocker cover on I can't. SO WEIRD!Does anyone know the right size for the washer that goes between the retaining circlip and the side cover? I don't seem to have one, so I may need to lathe one up. Link to comment Share on other sites More sharing options...
Waddy92 Posted August 12, 2015 Share Posted August 12, 2015 Fixed it. Spacer. Link to comment Share on other sites More sharing options...
KevtheRev Posted August 12, 2015 Share Posted August 12, 2015 Fixed it. Spacer. How ????? Link to comment Share on other sites More sharing options...
slice Posted August 13, 2015 Share Posted August 13, 2015 Yeah as above, been reading this and all you have to say is "fixed it"!!! WTF Link to comment Share on other sites More sharing options...
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