The frame number is pretty low, thats why i think its an 89. My frame number starts 283*** And is maybe a march/april built bike as the 3LN3's start at frame number 279*** My 1990 3LN3 has been stamped 1991 on the ADR VIN plate, as it was probably first registered in japan in 1991, but it's definately an early 1990 3LN3 (one of the first 4000 going by the frame number) so that's why my registration paper's say it's a 1991 If your bike was frame number 268*** to 279*** then i would think it could be a 1990 3LN1. Yamaha made 60,000 3LN1s so that's roughly 5000 per month, which is what i'm basing my thoughts on. Another thing, your bike may have gone out to a dealer and may have not have been sold and registered till 1990 (I'm pretty sure all the grey import bike's that came into Australia have copy's of the original Japanese registration paper's) which account's for the 1990 stamping on your Austrailian VIN plate
I really don't want to take the fairings off just to check the engine number. If my bike was made as in '89 as @my67xr stated, wouldn't that mean that it should have a 1HX motor ?
From the factory , yes ... but anything could be there after 30 years .... does it have the spin on/external oil filter just behind where the side stand is attached? .... 90 onwards had that instead of the underneath internal one
You only need to remove the rh fairing, 5 screws hold it on. The engine number should be stamped next to the 1HX just behind the clutch housing on the engine case on the flat rectangular pad. Should have the same last 6 digits as the original frame number, unless the engine has been changed at some point. All the engines from 1985 FZ250, FZR250, FZR250R and the 1998 FZX250s were 1HX (prefix to engine number) engines, think there were 4 different version of it with different cylinders and cams etc
You'd see the oil filter behind the kick stand switch if it were a 3LN3 or onwards engine. So it sounds like it still has a 3LN1 engine in it
Took the fairings off to try to fix whatever is going on with cylinder 4. I looked for an engine number and found "1HX" stamped on the engine
https://2fiftycc.com/index.php?thre...0-3ln-bodywork-frame-engine-carburetors.3469/ If you go to the forum heading for 4 cylinder Yamahas https://2fiftycc.com/index.php?forums/yamaha-250cc-in-line-4s.95/ You will see a list of stickied threads that contain a lot of information about your model.
Is that on the pad at the back right of the engine? So no number's next to the 1HX ? If not then it may have had a replacement engine fitted. From what i can work out they didn't have any engine number's stamped into them in Japan, the importer's here would just stamp the frame number into the engine casing so they'd match
Only problem is most of them look pretty well dead after the first 5 pages I'll double check when I get home from work, but yes I'm looking at the of one on the back of the engine.
The reason most thread's go dead after the first 5 page's is the person has either solved his problem, or sold the bike and left the forum. What info are you looking for in particular ?
Just general information. If I can't find what I'm looking for anywhere in the 100+ pages, I'll start another thread.
Some 250's had an engine number stamped at the lower left front on the engine looking from the front too