XL or XR 250 single with 4 valve head is there a head swap to a 2 valve head???

[craisin]

I can get a bike with head problems cheap was wondering?

[NordieBoy]

Would be much easier (eg possible) to get another 4 valve head.

I used to have plenty of 4 valve engine bits when I was racing mine so of course it never broke down.

What model year?

[ktm84mxc]

I'd put that idea in the to hard basket.
XR/XL went 4 valve in 1979 onwards, regig 83 with rfvc head design & twin carbs, 86 single carb & oil cooler this design carried over to all latter models.
Thousands were sold here u shud have no probs getting a 2nd hand head or complete engine, best you dig up your frame & engine number to get the correct year.

[craisin]

its a 1980 according to the old reggo on it

[NordieBoy]

its a 1980 according to the old reggo on it

Twin shock?

Will use a head from '79 to '82 and the CB250RS as well.

[neels]

Can't see any advantage to changing to a 2 valve head, and shouldn't be too hard to find a 4 valve one to fit, can tend to be a bit rattly in the cam department in their old age but still usable.

If you happen across a complete engine for not much, I might be keen to take the crank case off your hands, I really should fix the horrible noise in 2nd gear that I suspect is a missing tooth on my xl250.

[NordieBoy]

If you happen across a complete engine for not much, I might be keen to take the crank case off your hands, I really should fix the horrible noise in 2nd gear that I suspect is a missing tooth on my xl250.

Now, if you'd said that 4 months ago, I'd have had 3 spare sets of cases, 2 NOS gear drive counter balancer cranks (still in boxes), 2 6 speed boxes and a complete CB250RS 6 speed engine.

Now I've just got a TT350 instead :D

[neels]

Can't see any advantage to changing to a 2 valve head, and shouldn't be too hard to find a 4 valve one to fit, can tend to be a bit rattly in the cam department in their old age but still usable.

If you happen across a complete engine for not much, I might be keen to take the crank case off your hands, I really should fix the horrible noise in 2nd gear that I suspect is a missing tooth on my xl250.

Now, if you'd said that 4 months ago, I'd have had 3 spare sets of cases, 2 NOS gear drive counter balancer cranks (still in boxes), 2 6 speed boxes and a complete CB250RS 6 speed engine.

Now I've just got a TT350 instead :D
Bugger, too slow as usual :(

[NordieBoy]

Bugger, too slow as usual :(

So I won't say anything about the 3 pair of spare forks, spare shocks, spare frame, spare 23" front wheel...

[ktm84mxc]

You cud also check the wreckers & net in aussi as the XR range was the top seller there for many a year in the early 80's, farmers just loved them.

[warewolf]

in aussi as the XR range was the top seller there for many a year in the early 80'sand late 80's, and early 90's, and late 90's, and...

[craisin]

Twin shock?

Will use a head from '79 to '82 and the CB250RS as well.

Yeah thats it twin shock unit
The motor goes but backfires all the time:ar15: