mspenz Posted January 21, 2016 Report Share Posted January 21, 2016 I have a 99' Techno which I'm really getting to like and so am slowly replacing various seals / bearings etc to get it and then keep everything in good order. I've taken the top end apart to do a proper decoke, replace small end bearing and have also splashed out on a set of rings. The barrel and piston seem to be in good order with no scoring or scrapes so I have just given the bore a light hone to help the rings bed in, my only concern is that there a couple of small pitting marks in the con rod bearing face. I realise that this will have to get replaced soon but I'm going to run it for a while first before doing a bottom end rebuild and I was wondering if there are any alternatives to the £200 conrod kit from Trials & Tribs Main bearings / gearbox bearings are readily available but is there anyone who can re-condition the conrod / crank for less? This was a cheap bike that has cost around £250 so far but I do like it and they just feel quite solid and planted...so I will spend more over time and get it to a standard that will make it easier to maintain, it's frustrating though that some parts for these older Betas' can cost silly money! Quote Link to comment Share on other sites More sharing options...
suzuki250 Posted January 21, 2016 Report Share Posted January 21, 2016 honed the bore, is not plated? Quote Link to comment Share on other sites More sharing options...
suzuki250 Posted January 22, 2016 Report Share Posted January 22, 2016 (edited) If you have any pitting on the big assembly then it needs a rebuild, and if you have put a hone in a plated bore you have probably done some damage If it was a cheap bike, it might be worth just running it until it gets noisy? The other option is find a good used crankshaft, try Steve Goode MC’s Edited January 22, 2016 by suzuki250 Quote Link to comment Share on other sites More sharing options...
pschrauber Posted January 22, 2016 Report Share Posted January 22, 2016 The coating inside the con-rod is mostly hardchrome, there are manufactors that will recoat the con rod and pin if in need but it's a one off custom hardchrome ... I personal had made very good experiences with Wissing Hardchrome in Germany, they do all kind of hardchrome, mostly to big machine equipment and gears weightening several tons but too motorcycle stanchions (hint hint). They would rechrome the surfaces, grind and polish them to your spec's but I believe it will be at least as costly as a new one. The web page of Wissing, (the pictures of what they hardchrome are quite interesting ...): http://www.wissinghartchrom.de/bilder-galerie.html 1 Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 22, 2016 Report Share Posted January 22, 2016 £200 for a near obsolete conrod isn't bad, A second hand bottom end from a breaker will set you back over £100 and will be well worn also. I replaced one on a 2014 Sherco and it was £250 Just for a conrod kit. Just ride the bike and don't worry about it, if it goes bad chuck a rev 3 lump in and sell the remains of your old engine bit by bit, you will make good money on it as the bits are hard to get now. 2 Quote Link to comment Share on other sites More sharing options...
mspenz Posted January 22, 2016 Author Report Share Posted January 22, 2016 Plenty of good advice there, I'll continue to run it for a while and see how things go 1 Quote Link to comment Share on other sites More sharing options...
mspenz Posted January 22, 2016 Author Report Share Posted January 22, 2016 If you have any pitting on the big assembly then it needs a rebuild, and if you have put a hone in a plated bore you have probably done some damage If it was a cheap bike, it might be worth just running it until it gets noisy? The other option is find a good used crankshaft, try Steve Goode MC’s You should always scratch in a glazed bore when fitting new rings regardless whether or not it is nikasil, a 'light' hone means exactly that and it's something that you can more or less do with maybe 300 grade wet and dry by hand. This isn't removing any material it is only providing a key in the bore for oil to catch on so that the new rings can bed in properly without the risk of nipping up on an already glazed bore. I'll keep playing meantime but also keep an eye on the used market, my feeling is that if I recon the bottom end myself then at least I know what I have, I could buy something used and still end up with problems as not everyone looks after their toys and I am pretty fussy when it comes to doing things right! Quote Link to comment Share on other sites More sharing options...
worldtrialchamp Posted January 22, 2016 Report Share Posted January 22, 2016 Quote Link to comment Share on other sites More sharing options...
mspenz Posted January 22, 2016 Author Report Share Posted January 22, 2016 (edited) Interesting stuff! A quick Google shows that there's an enormous conflict of opinions on this and everyone has an opinion.. I was also advised to do this by someone in the industry who runs a large business and is involved in building/repairing and competing in trials, if it was a modern state of the art machine then fair enough but on a 16 year old Techno!! These guys are offering a straight replate, piston kit and top end gasket set for around £180 for a 250cc...not so bad. http://firefoxracing.co.uk/engine-servicing/ Edited January 22, 2016 by mspenz Quote Link to comment Share on other sites More sharing options...
steve_earle Posted January 23, 2016 Report Share Posted January 23, 2016 It won't hurt to run a scotch brite round the bore in a similar pattern to the honing, It will help bed the rings in uniformly. A shiny bore will just polish the rings rather than wear them to the shape of the bore for a better seal. As others have said there's a lot of debate around the net on this along with running in. 1 Quote Link to comment Share on other sites More sharing options...
suzuki250 Posted January 25, 2016 Report Share Posted January 25, 2016 I appreciate the principles of honing a bore, but I wouldn’t fancy putting a hone down a worn plated bore as it would probably cause blisters or chipping on the port edges. Quote Link to comment Share on other sites More sharing options...
crazybond700 Posted January 25, 2016 Report Share Posted January 25, 2016 Maybe just run the bike, if no problems occure until now. Quote Link to comment Share on other sites More sharing options...
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