jinxed

My 20 year old engine is on it's last legs/bearings/whatever. I've kept it going with parts from a later engine, probably 10 years old. Mechanically, the two engines are identical so it seems. I've got another engine, also ~10 years old, that I've just put back together. I note that the connector blocks on the generator/ignition pickup are different. Rather than hack off the connectors and wire up the new engine to the old loom, I thought I'd just use the whole engine casing/cover from the old engine mounted to the newer one. (The casing houses the generator and ignition pickup.) I will need to look at the magneto thing, to see if they are the same I guess. Also, the newer carb has a single eletrical spade connector and the old one doesn't. Again, to keep things simple I will re-use the old carb. No idea what this connector is for; a wiring diagram would help I suppose. (Yep, I've done all my recent engine repairs/rebuilds without a manual; and I wonder why it's kn*ckered!) Anyone tried this swop before and have any useful tips or comments for this model?

And there was me just about to shout "broken valve", "BROKEN VALVE". I have two SR125 engines that have broken valves (one broke the inlet, the other the exhauset I think); I've not had this trouble on any other bike I hasten to add. I wish I knew why they break; mine broke right at the top where the spring retaining washer sits. I can only guess that the frequent banging causes them to work-harden and go brittle. Maybe if the clearance is too wide, they work-harden faster than they should. (My feeler gauges are rusted real bad & I can't tell which is which anymore!) One of my heads has a damaged valve guide too; maybe this increased the friction on the valve, putting it under more stress. Maybe? As it was a 20 year old bike, I just threw a new valve in & crossed my fingers. (I.e. ignored the damaged valve guide.) 4 weeks later the camshaft gear slipped, which put the timing WAY out & the piston hit the valve and broke the rocker arm. I could go on ....... it ran out of oil recently & seized ....... How much more can this engine take!! $840 is a big ouch! Is it not cheaper to get 2nd hand engine? (Hence I now have three engines in various states of disrepair.)

As it's your first bike, walk away & put it down to experience. If he's lyin about it being Cat C, what else is he lyin about? ("Three bikes, actually Ron.") If you're a confident mechanic, you're familiar with this model and you can get it for a song, that's a different story. Remember, you may not be able to sell it on in the future either. You already looked at the bike, right?

I'm pretty sure that my local friendly bike garage said the bottom end is the same; presumably the gearing is different though. (Either in the box or the final drive.) This suggests that the stroke is the same, so if it's true the 250 engine should be about the same height, suggesting it will sorta fit. I'd be worried about the rest of the chassis handling the extra power though. (All those with the drum braked model prepare to carry spare underwear!) Not to mention what your insurance company will say. Best to keep it reasonably stock I reckon. Now does anyone know if the XJ600 engine will fit the SR125 frame??