2 Strokes Down Under

Hi there,

Like the title says I'm in Melbourne and have had a 250LC sitting around begging to be rebuilt and ridden for far too long. Originally a cheap purchase off Gumtree that was rough but running, a few laps at the Broadford Bike Bonanza shortly after saw to the end of that, with it seizing up at the end of the bottom straight. It has sat in the corner of the garage for a few years now, but after my most recent track day and seeing a couple of 350LCs, and with a mate rebuilding his RGV250 I've decided life's too short and I should get this bike up and running again for some track fun and Club rego it. Needs the crank rebuilt as the left rod is nipped up, can't remember how bad the barrels are but will pull them all out and get them on the bench to have a look at in the next week or so to get reacquainted. Need to get an XS650 engine off the bench first to make some room, yet another project that has sat too long!

Seems like forums aren't as popular as FB these days, but I much prefer them so thought I'd join up. I'm guessing this board is not too active, but thought I should sign up anyway if I'm going to trawl through old posts, and maybe find some help along the way as I rebuild.

Cheers .. Jules

Welcome Jules, this is a quiet forum, but it is local

Id say you will need to rebore and fit new pistons if youve seized it and assuming you want some longevity, the parts are not too exy really.

Only buy OEM crank seals no matter what other advice you choose to ignore.

Link on this forum is in vic and does cranks for members.

Parts are getting harder to find now for the LC as the prices have gone a but mental the past few years. but you should find all you need.

Welcome to the forum. I still have my 250LC track bike. A few members on this forum to help with LC questions.

Thanks for the welcome chaps. Nice to find a local forum, even if it is quiet.

JonW - what you have outlined is the plan for my rebuild, thanks for reinforcing my thoughts. I was lucky enough to pick up a spare motor at a swap meet a few years back, along with a few extra side covers. From memory the left rod felt a smidgeon tighter than the right, but it rotated and the price was right so thought it would also be a good candidate for a rebuild/donor. Glad I bought it some years back when prices were not crazy. I have seen mentions of Link regarding crank rebuilds and will reach out to him as he seems well regarded.

mboddy - the few laps I did on the bike at Broadford were fun as it was so light and chuckable compared to the portly XS650 I had been piloting in the earlier sessions. Would love to get it ready for the return of the Broadford Bonanza this year but will need to get a crack on. I would like to keep the bike fairly stock but wonder if you could recommend any upgrades for a bike that will see the track as well as the road? I'm thinking rearsets may be one of them. Also finding good tyres that fit the stock rims is probably my first priority, once the bike is running.

Service the front brake and replace the original brake line with a braided one (original rubber one has service life of 8 years). Remove the centre stand.
When I next race mine I will be fitting Avon AM26 Race 90/90x18 front and rear tyres. They are a bit pricey but they are the correct fit for the 18"x1.85" front and rear rims. I have raced with Bridgestone BT39SS 90/90 rear and know that you don't need any wider. A wider tyre is pulled in too much by the narrow rim and so you get less tread on the road.
Pod type air filters give issues with the stock carbies but you can get a better result by drilling lots of holes at least 12mm diameter in the airbox lid and increasing the size of the main jet to match. Stock jet is 190. If your bike doesn't have any problems then you will want it to be somewhere between 205 and 230. Try the largest one first and come down a size at a time until it is not too rich up top. If you are keen you can raise the exhaust port 1.5mm, just use one side of the stock head gasket (sprayed with copper paint) and retard the timing to 1.7mm BTDC and NGK 9 plugs. I have always used modified Suzuki RG250 exhausts on mine but TYGA now make some very nice crossover pipes for the 4L0.

Thanks for the excellent information mboddy. Luckily the bike came with a HEL braided line up front, so some savings there for the caliper parts. Hot tip on the tyres, they look pretty flash. Will definitely have to get it up and running on the stock carbs, airbox and pipes before looking at further mods. Those TYGA pipes look pretty sexy.
Removal of the centre stand is a smart move, I will need to find a side stand as this bike did not come with one. Have read some poor reports of the Yambits one so hopefully can find one somewhere else...

Im not sure how the Tyga pipes would perform as they are 350 pipes, but they could well be the bomb on a 250, I just dont know anyone who has tried any yet.

If you have a spare center stand going im all ears

If you find that you need new chain and sprockets you should convert to 520.

Welcome Jules, there are plenty of good folk on this forum who will happily share their knowledge with others, so be sure to ask any questions you need to.

Good luck with your project and please keep us posted.

Thanks for the extra tips, that's a good one on the chain. I'll stick to stock pipes for the moment, just would be happy to have a reliable ride in the near future.

JonW - Sorry I won't be parting with the centre stand, just too handy for a road bike! If I take it off, it will just be for track days.

There's a lot of info on here to wade through, got in touch with Link yesterday and will send him my crank once I've taken it out. Is Yambits ok for crank parts (webs,pins,bearings)? Pro-X for rods, piston kits? I'll stick to genuine for the seals and headgasket, and probably aftermarket for the rest of the gaskets.

Yes, Prox and TKRJ etc is fine for pistons and rods from yambits. I know some usa based crank guys who use the crank web parts from yambits, but not used them myself. your own parts should reuse if not totally screwed. see what Link says first perhaps.

FWIW OEM gaskets tend to be ok prices in Aus, check the online dealers and search on part numbers. bearings and other parts are usually cheaper elsewhere. Have a read on this forum and you should glean a bunch of info on where we buy parts etc.

No worries on the stand, always worth an ask

Thanks again for the info JonW, will see what needs replacing once Link has a look at it and go from there. Will need to start collating a parts list over the next few weeks. A bit of reading ahead of me. Cheers!

Welcome Jules!
Not much I can add that hasn’t been covered, but there are helpful and friendly people on here, all over Australia.