82 RM 250 head differance 82-84

[yellowsnow]

i couldn't find a head for my 82 rm250 restore project, but i found a 84 head and bought it. but i was told that the 82 head would give the best performance......But i read some history about the RM 250 that said 82 was fast then in 83 the head had a bad squish, then the 84 was basically a copy of some MX racers 83 race bike. like suzuki copyed it and produced it for 84. even back then everyone new the 82 head was better so that MX racer would've been using a 82 head making 82 and 84 cylinder heads identicle??? if this is all true. but they do have different part numbers, any insight on this would be helpfull thanks takin the lower end to the shop for new bearings and seals on tuesday

[no1clyde]

I have a 82 head and a 83 head, the 82 head is a shallow dome with no squish band and the 83 has a squish band and a deeper dome. With the 82 head it hits harder and rev a little higher. With the 83 head it is smother on the hit but runs fine. I have never seen a 84 head but a friend of mine had a 85 and as I remember it looked the same as the 83 but could be wrong.

Ed

[resurrection]

Just don't loose your head

[Phil Hannah]

The hot ticket was to put the 82 head on the 83.Dont know about the 84 head, but none of them ran like the 82. That bike ripped for that era.Just watch out for broken clutch plates and stay on top of swingarm bearing greasing. I had 81,82,83,and84.Ah,the good old days.

[rayivers]

Here's a pic of the '82 and '83 RM250 heads side by side. The '82 is on the left.

The '83 head is about 1/4" taller than the '82.

It seems to me like the '82 combustion chamber is really just one big squish band.

Ray

[yellowsnow]

wow great referance pics

[yellowsnow]

i can't remember if the 84 head i bought has a dome or not .. i'll just have to see when it gets here.

[ss440gp]

I had a 82 and a 84 and the 82 was faster and hit harder, it to this day, it is the funniest bike I ever owned. The 84 was better than the 83 but still wasn't a 82. I would look for a 82 head. It could get a little twitchy in the fast bumpy sections but man did it turn. Great bike wish I still had it.

[yellowsnow]

so the head made all the difference?? i got the 84 head in and it looks just like the picture of the 83 head. a guy on TT said he has one he can sell me. but i'm takin the lower end to the shop tomarrow for new rod and main bearings. among other things i still need for it. i hope he still has by the time i have a little extra money for it. probly one of you guys i don't remember the name... hold on to it about 2 more weeks please.. i wish i could have separated the cases myself and saved some money, but the main bearing were solid to the crank. i had it split except for that.

[rayivers]

That was me with the head. I just stuck it back in the cabinet, it's not going anywhere. It's been good having it as a spare, actually.

That's the good news. The bad news is the article below, which may make you want it more than ever... ? (just kidding) It's an article on getting an '83 RM250D to run like an '82. According to them they succeeded and then some, ending up with the best of both bikes.

You may have to copy it and open it in a photo editor, as the type looks pretty small. It's missing the opening photo, but is otherwise complete. I also have the original .pdf file.

Ray

[yellowsnow]

good read. i lust realized from reading that that for this 84 head to bolt on i would probly have to change the studs because they would be to short....well i'll just see how bad the suzuki shop hurts me tomarrow... i've got a long list of parts i need....i think i'm gonna put the reed valve assembly out of my husky 250 in it. the ones i have for the suzuki are rusty junk. the husky reed cage fits great just need to drill bolt holes (in the reed cage mounting lip) in the right spots. i have a ohlins rear shock off this husky that measures the same eye to eye, think it would be way to stiff?