al_orange Posted July 16, 2016 Report Share Posted July 16, 2016 My bike is making a pretty bad tapping/knocking, which I hope is piston slap rather than bottom end (because it used to do it when cold but now does it all the time so is getting bad).... anyway, I thought I'd have a quick look over to see about taking the cylinder off but have fallen at the first hurdle - removing the header! I know this has been discussed before but the thread with the info doesn't have the pictures anymore. So - what tools and methods are needed to get to the allen bolt that's covered by the curve of the header? Also - It's a 2001 270 Rev 3 - will I be able to take the cylinder off with the engine in the frame? It looks pretty tight in there. Thanks. Quote Link to comment Share on other sites More sharing options...
madmostin Posted July 16, 2016 Report Share Posted July 16, 2016 Ball ended Allen key. Hopefully it would have been put in with a bit of grease previously. Cylinder can be removed but radiator needs moving to make way. 1 Quote Link to comment Share on other sites More sharing options...
lineaway Posted July 16, 2016 Report Share Posted July 16, 2016 Cut off an allen key and use a wrench on it. 1 Quote Link to comment Share on other sites More sharing options...
2stroke4stroke Posted July 16, 2016 Report Share Posted July 16, 2016 You should be able to remove the barrel with the motor insitu but, presumably due to a combination of production tolerances, I was not able to do so with my Beta as the top motor mount fouled the underside of the tank. Good luck with the sumpguard if you end up having to remove the motor. 1 Quote Link to comment Share on other sites More sharing options...
al_orange Posted July 16, 2016 Author Report Share Posted July 16, 2016 Thanks for the info. I've done a fair bit of staring at the engine and it does look like a very tight fit. I've tried a straight allen and it won't go in, so a ball end is the only real option. Now I don't know whether to risk taking it apart as I have events for the next three weeks including a weekend away.. Do I risk missing them all or lunching the engine properly.... next question - piston size, presumably if it's slapping then it's likely to need a bigger piston?? The bike is 15 years old and I wouldn't be surprised if it is on it's original one. The previous owner did not look after it well. Quote Link to comment Share on other sites More sharing options...
dan williams Posted July 16, 2016 Report Share Posted July 16, 2016 Allen key with the short side cut even shorter works for me but it's still a pain. 1 Quote Link to comment Share on other sites More sharing options...
copemech Posted July 16, 2016 Report Share Posted July 16, 2016 (edited) Thanks for the info. I've done a fair bit of staring at the engine and it does look like a very tight fit. I've tried a straight allen and it won't go in, so a ball end is the only real option. Now I don't know whether to risk taking it apart as I have events for the next three weeks including a weekend away.. Do I risk missing them all or lunching the engine properly.... next question - piston size, presumably if it's slapping then it's likely to need a bigger piston?? The bike is 15 years old and I wouldn't be surprised if it is on it's original one. The previous owner did not look after it well. New pistons are matched to the cylinder by re-plating and diamond hone to the proper fit. You send the piston in with the barrel to the platers, takes several weeks in most cases. Installing a larger piston in an old bore is a waste in most cases. Edited July 16, 2016 by copemech Quote Link to comment Share on other sites More sharing options...
lineaway Posted July 17, 2016 Report Share Posted July 17, 2016 Allen key with the short side cut even shorter works for me but it's still a pain.No. you cut off about an inch from the long side. Use a wrench or a socket with the universal joint. Easy peasy if you have a cut off wheel/grinder or a chop saw! Think out of the box. Quote Link to comment Share on other sites More sharing options...
al_orange Posted July 17, 2016 Author Report Share Posted July 17, 2016 (edited) Just had a tinker - only two options for the header - 1. Remove the radiator and frame spar things or 2. Ball head allen. There simply isn't enough room to do anything else. I'm optimistic though because I took off the fly wheel cover and the fly wheel is absolutely rock solid and very smooth to turn so I'm hoping it's just the top end. I don't think I'll be replating the cylinder at this point as the whole bike is worth about $1000 IF someone was daft enough to buy it but if I can resolve the rattle with a new piston then I'll think about a replate in the very near future (after the upcoming events). It's quite satisfying being a novice with an old crap bike, if I ride a brand new one, people might expect me to know what I'm doing! Edited July 17, 2016 by al_orange Quote Link to comment Share on other sites More sharing options...
al_orange Posted July 17, 2016 Author Report Share Posted July 17, 2016 (edited) And for me, the answer is - Ball Ended Allen Key. Absolutely no problem taking it off at all. Took longer to write this post than to remove the header. Thanks very much for your help. I did have to remove the radiator to get the cylinder off, I had to rotate it on the piston to clear the tank so that might be tricky getting it back on.. I'm pleased that the bottom end seems fine. No detectable up and down play.. The small end is a different matter. There was lots of play between the wrist pin, small end bearing and the con rod. It has an A piston and cylinder. The cylinder does have detectable wear at the top and bottom but otherwise is in remarkably good condition. The piston is well worn too but again, nothing worrying, just hours on the engine. I think I will contact Langcourts and see about getting a replate as the engine is in better condition that I expected so I might get a bit more out of her yet. I've rebuilt/replaced much of the bike outside of the engine except the rear shock, so she's getting better with age. lol. Edited August 4, 2016 by al_orange 1 Quote Link to comment Share on other sites More sharing options...
dadof2 Posted July 17, 2016 Report Share Posted July 17, 2016 Putting in a new piston without a replate on a rattling engine is a total waste of time and money. 1 Quote Link to comment Share on other sites More sharing options...
al_orange Posted August 4, 2016 Author Report Share Posted August 4, 2016 Just to update and close the loop in this one - I sent the cylinder to langcourts for replating. It was very close, timings wise but I ended up collecting the cylinder - as expected, it looked like new. I rebuilt everything last night. It took 2 hours because I am pretty methodical (and ham fisted..) the only tricky bits were getting the rings compressed and making sure they were around the location pins and then tightening the head bolts as access with a torque wrench was impossible to two bolts. Have run it up to temperature twice now and it all seems right. It seems to get the fan going a bit quicker that before but then it's pretty warm at the moment. The rattle has completely gone and the engine feels so much smoother now. I went with a 1mm base gasket and that's softened it a bit too. So apart from the time I spent waiting for parts and replating, it took about 4 hours from start to finish and was very straight forward. Will be putting a LOT of hours on the new top end this weekend so fingers crossed I've done it all ok... 1 Quote Link to comment Share on other sites More sharing options...
dan williams Posted August 8, 2016 Report Share Posted August 8, 2016 Success then. May it give you many happy hours of dependable power. Yeah those two bolts are damn near impossible to torque. I think I had to resort to a crows foot and some calculation. 1 Quote Link to comment Share on other sites More sharing options...
al_orange Posted August 8, 2016 Author Report Share Posted August 8, 2016 Thanks Dan. I'm hoping it will give me at least a year of decent service.... especially after I completely submerged it in a river and filled the engine with dirty water two days after rebuilding it... aaaahhhhh! Quote Link to comment Share on other sites More sharing options...
2stroke4stroke Posted August 8, 2016 Report Share Posted August 8, 2016 Could be worse - someone did that to a 4RT this weekend. Quote Link to comment Share on other sites More sharing options...
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