dr nick Posted March 28, 2004 Report Share Posted March 28, 2004 (edited) Following on from my previous post about the cooling system on my 98 Techno. I stripped the top end down and replaced all the gaskets and O rings and checked everything out ,like the waterpump was working properly. While I was at it ,I changed my clutch fluid (again) ,filled the cooling system with the correct amount of fluid and gave the bike a general clean up ready for a ride today,then stood back and admired my work for an hour or so. When I got to my practice area the bike started second kick and sounded great...then it started with a metal on metal grating noise after only 10 seconds.I quickly killed the engine and pondered on what I had done wrong the previous day. When I got it home I asked a mate to give me a second opinion ...started it up ...grating noise straight away ,sounding like bits of metal loose somewhere flying about His opinion - Bottom end is knackered He`s going to get a friend of his to give a third opinion ....but listening to it ,I dont really want to start the thing up again for fear of causing more damage. Is there any way af checking if the bottom end is knackered without starting it up again Is putting a new bottom end in ,as difficult a job as my mate made out (ex Motocrosser) or is it quite straight forward.I have no experience of this so have no idea . As always ...any help greatly appreciated regards N Edited March 28, 2004 by Dr Nick Quote Link to comment Share on other sites More sharing options...
beta boy Posted March 28, 2004 Report Share Posted March 28, 2004 sounds like when my mates dad rev3 bigend end bearings whent the disintergrated leaving the balls shattered in the bottom it is not that expensive about 80 to get it fixed if that is all that is wrong but it is not didficult just time consuming Quote Link to comment Share on other sites More sharing options...
techno98 Posted March 28, 2004 Report Share Posted March 28, 2004 if your under the illusion that it costs 80 quid or so than ur gonna be in for a big shock when you get the bill unless u know how to split an engine in 2 and have a 10 ton press handy in the loft. I take it u dont know how to do this so there is a number of other problems that you may have to consider. if the ball bearings of the bottom end have been crushed and have gone where the hell they want then they may have scratched the bore which will mean a re-crome. this is about 120 quid. the actual bearing is only about 30 quid and is available from bvm moto. if you have to split the engine than you will also have to get a new gasket kit. if you describe the sound as scratching than it is highly likely than the bore has been damaged and this ialso means a new piston and rings which is another 65 quid. Sorry if ive made you feel bad but at least it wont come to you as such as a shock if any of the above mentioned situations have occured. Quote Link to comment Share on other sites More sharing options...
stevel Posted March 28, 2004 Report Share Posted March 28, 2004 Don't be too pessimistic, my experience tells me it is impossible to diagnose a noise by phone or email! Get someone who is knowledgable to have a look at the bike. If its any consolation I would be surprised if it is the bottom end if it started and ran for 10 secs OK, May be you just cocked up when you had the cooling system stripped. One thing worth trying, take the plug out and turn the engine over slowly with the kickstart and ssee if you can find the source of the noise Quote Link to comment Share on other sites More sharing options...
brucej Posted March 29, 2004 Report Share Posted March 29, 2004 The best way to check the bottom end is to pull the top end off and have a look. I wouldn't risk starting it again until the problem has been found, it can only get worse by running it. Hope it's not too serious! Quote Link to comment Share on other sites More sharing options...
rev3guy Posted March 31, 2004 Report Share Posted March 31, 2004 Not worry mate. Splitting the cases is not as bad as it might seem. Ya dont need a 10 ton press but ya will need an impact driver to get the flywheel off, suggest if you attempt to split the case that you look for the Aussie trials web page that has a breakdown of the engine, very helpful when putting it back together. As for main bearing removal and replacement try this method (I just did it and worked great), pre-heat the oven in the house to 93C/200F, after you remove seals, set cases in over for about 10 mins, take out and turn over and bearing will fall out or pop out with easy tap, be careful to not damage cases. Same goes for new bearings, put new bearing in freezer for 15-25 mins, cases in oven and bearings will drop right in, no need for press. Also make sure you mark the position of the stator before removal, will make easier to put back together. You might need a third hand when putting cases back together, especially with the trans shafts. Also when taking apart make sure you have a few plastic wire ties handy, when removing the gears wire tie everything back together in the order of removal, this way parts/pieces dont get mixed up and reversed. Good luck and remember to take your time and have fun. Quote Link to comment Share on other sites More sharing options...
clarkp Posted March 31, 2004 Report Share Posted March 31, 2004 So you had the top end apart... did you change the rings? did you drop a circlip into the cases? Did the rings get seated properly or did you have trouble getting the jug back down over the piston / ring assy? Since you are familiar with pulling the top end down - I'd do it again and check things out before you DO have a problem with the big end. Either way, you better break into your beer stash to pay for this... Quote Link to comment Share on other sites More sharing options...
dr nick Posted April 1, 2004 Author Report Share Posted April 1, 2004 Clarkp - No i didnt change the rings ,but had the head off again and everything seems ok in there,Even the conrod doesnt seem to have any play up and down. still awaiting on the "3rd opinion" on what it may be ,till then I`m going to twiddle me thumbs just had a new phone,so working on how to work it will keep me busy for a while regards N Quote Link to comment Share on other sites More sharing options...
the artist formerly known as ish Posted April 1, 2004 Report Share Posted April 1, 2004 98 had some bad cast kickstart gears, and a tooth would break off, don't start the bike!! if the tooth pics up it could ruin the dummy gear and clutch basket ring gear. You do have to remove the outer and inner clutch cover to see if it is missing a tooth, and to inspect all the other kickstart related gears for damage while you have the covers off, it's not that big of a job. Also if it is missing a tooth you need to make sure you get it out of motor it should be in that side, of the motor in the oil, so check the oil as you drain it out. Quote Link to comment Share on other sites More sharing options...
dr nick Posted April 3, 2004 Author Report Share Posted April 3, 2004 (edited) 98 had some bad cast kickstart gears, and a tooth would break off, don't start the bike!! if the tooth pics up it could ruin the dummy gear and clutch basket ring gear.You do have to remove the outer and inner clutch cover to see if it is missing a tooth, and to inspect all the other kickstart related gears for damage while you have the covers off, it's not that big of a job. Also if it is missing a tooth you need to make sure you get it out of motor it should be in that side, of the motor in the oil, so check the oil as you drain it out. On that note Ishy - I`ve changed the clutch oil a few times recently and found a few bits of metal stuck to the magnet on the drain screw every time ....could this be why ????? Regards N Edited April 3, 2004 by Dr Nick Quote Link to comment Share on other sites More sharing options...
charliechitlins Posted April 4, 2004 Report Share Posted April 4, 2004 Nick! Listen to Clark. Coincidences do happen, and your lower end could have grenaded after doing the work you did, but 999 times out of 1000 whatever problem you have is directly related to the last thing you messed with. Did you just have the head off? I assume not because you say you checked the rod. Wy did you strip the top? Inspection? De-carbon? Did you try to move the crank side to side? If your lower end is really whipped, you should be able to feel play at the flywheel. Ishy's advice on the kicker gear sounds good, too. That would be another coincidence. Quote Link to comment Share on other sites More sharing options...
dr nick Posted April 4, 2004 Author Report Share Posted April 4, 2004 Charlie - I took the barrel and head off to change the gasket and o rings .....because it was making the "metal on metal" grinding noise,and assumed it was because it was overheating due to a coolant leak(it was only 2/3 full when I checked it). while it was off ,I gave everything a clean and reassembled it ...I always try to be meticulous(sp) after having a replate ,piston and rings last year. when I started it up ,it sounded just as bad as it was the week before,but after only 10 seconds ....not after about 10 minutes like the previous week. I do remember a while back though ...my wifes car did the same thing when a front wheel bearing was shot .It made the same sort of noise after driving for a while ....when the bearing had heated up with friction so I`m going along with that at the moment ,until someone can check it properly Thanks for all the help everyone Will update when I find out exactly what it is regards N Quote Link to comment Share on other sites More sharing options...
dr nick Posted April 13, 2004 Author Report Share Posted April 13, 2004 Took the bike to my nearest dealer today (an hour away)- He said some bearing or other was knackered ,on the left hand side (whatever that is).....they are known for it apparently. After starting it up he told me to touch the footpeg ....you could feel the vibration of the knackered bearing through it ,even though it didnt feel any different from when I first got the bike to me.Maybe it was knackered when I got it. I`m going to be Quote Link to comment Share on other sites More sharing options...
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