Mugen performance package - Air R.

[PLJ.]

Somewhere on the net a few nights ago I saw a complete Mugen big bore kit for sale for the air 250R's. The kit had the pipe, big bore ported cylinder, piston, rings, gaskets, Mikuni carb and a few other pieces all NOS and never used!! I wonder if this kit is different than your standard 300cc HRC kit that can be installed in these models?? Anyone have a Mugen kit on their R?? Over the years I have seen Mugen 250R pipes that would only fit special Mugen cylinders. Most of these parts I have seen date back to the air R's but I did run across a person who has a real Mugen cylinder for a liquid 85 R and another person who modified an 84 or 85 CR250R Mugen pipe to work on his liquid R. Anyone have any of these parts?? or is this package for sale somewhere here on this board?? Asking price for the kit was $1,600.00 Thanks.

[dunerash]

Somewhere on the net a few nights ago I saw a complete Mugen big bore kit for sale for the air 250R's. The kit had the pipe, big bore ported cylinder, piston, rings, gaskets, Mikuni carb and a few other pieces all NOS and never used!! I wonder if this kit is different than your standard 300cc HRC kit that can be installed in these models?? Anyone have a Mugen kit on their R?? Over the years I have seen Mugen 250R pipes that would only fit special Mugen cylinders. Most of these parts I have seen date back to the air R's but I did run across a person who has a real Mugen cylinder for a liquid 85 R and another person who modified an 84 or 85 CR250R Mugen pipe to work on his liquid R. Anyone have any of these parts?? or is this package for sale somewhere here on this board?? Asking price for the kit was $1,600.00 Thanks.

I'm running a w/c Mugen cyl and head on my '85R. I have ESR exhaust flange and LRD pipe. Everything fit fine.

[MTS]

i thought the mugen kits fior the air where 360's? anyways, the mugen has far superior portuing over the HRC i would think if its tradidional mugen style, for 1600 bucks i would jump on it, they are extremly hard to find,let alone NOS never used...will make that R SCREAM...

[PLJ.]

You were correct. It is a 360cc kit. Includes: Cylinder, piston, head, gaskets, reed cage, reed spacer plate, Mikuni Carb, Expansion chamber and a few other small items. NOS, it also states that the cylinder is Nikasel plated, which must have been done at a later date. Looks like quite a nice package. I should buy it.

[deathman53]

you also have to bore the cases and does it include the special tranny gears?

[PLJ.]

I did not see any gears in the pic. Was there a special gear package also?? After looking a bit closer I did notice an intake boot and a different exhaust flange in the package. Deathman, what about the case work?? Who around can still do it?? Thanks.

[deathman53]

I have a add for the 360 mugen kit and it says stage one: cylinder, head, piston, rings, gaskts, pipe, tank mount, cluth springs, Stage 2: all stage one, plus 36mm carb, reed spacer, twist throttle, airbox cover(vented), silencer, 14t sprocket. Case machining& crankshaft rebalancing for 360 kit:$150
I do't know anything about them, except what I read. I seen the 360 dirtbike kit and that included tranny gears also.

[MTS]

I did not see any gears in the pic. Was there a special gear package also?? After looking a bit closer I did notice an intake boot and a different exhaust flange in the package. Deathman, what about the case work?? Who around can still do it?? Thanks.

Any reputable machine shop should be able to do it,...personall i would Call ESR and see if they can help you out...they seem to have Alot of experiance in the 250's...www.esr250.com

[Old 179]

On the 360 kit, stage one cost $650 (in 1984 dollars) Stage two was total of $850.
The machine and balance work was additional $150 like was said.
There was a 250 kit also.Includes 250 Pro porting $135 (your jug?) Cut base cylinder deck height $10,Boost ported mugen piston $10,250cc motoplat ignition $175, 250CC Mugen power pipe $120, Competition shock mod and increase travel $75, Fork spring kit $24.99

[dunerash]

Nice info.. Thanks I didnt know how much of this stuff was still out there

[hrc85250r]

that kit is nuts, its actually theoritically wrth that exact amount in 2005 dollars check it out http://www.westegg.com/inflation/

if it costs 850$ in 84' it would cost 1573.33$ in 2005.

awesome deal, if you got the money, buy it.

[Troll 2]

Gotta like the old school stuff. Good luck.......

[PLJ.]

I spoke with the seller of this kit recently. He is a very knowledgable person on all Mugen parts and old Honda parts. He said that the "internal gear" that was available in these kits was not really for the ATC motor. This gear was an updated "solid hardened" replacement to fix a breaking problem in the 1978 CR250R motor. He states that the ATC 81-84 motor already has this "updated" item installed in the factory. Apparently, Mugen sold a similiar kit and probably more of them for the 78-80 CR250R's. This kit had the "special" gear in it to udate a 78 motor. The CR kit looks very similiar but the bolt patterns are slightly different. These were the hot item back in the day because Honda did not offer an open class bike to compete in motocross at the time. I was also informed that there are two of these kits installed on ATC's known at this time. One is in Calif. and the other is in Wisc. somewhere with many other 360's kits on CR's running in the vintage seen. They have proven very reliable and very powerfull, or so I have been told. Wiseco will even make overbore pistons for them!!

[250rBeast]

Mugen made a 360cc kit and a 250cc kit for the aircooled 250R. Danny250r, who is a member here and at 3wheeler.org has the mugen 360 on his 81 250R. I myself have been looking for one, mugen was way ahead of the times with their products. Another fact is, Mugen was created by people related to Honda, I believe it was Mr. Honda's son but I don't quite remember at this moment I'd have to check my references. I have a mugen pipe for my 84 250R.



Dannys signature:

Honda ATCs kick @$$
81' Honda ATC 250r ported, shaved head, Boyesen Pro Series Reeds, K&N filter w/mod airbox, DG national Pipe, Wiseco Hot Rod, 360cc Big Bore kit by Mugen Power
85' Honda ATC 200S (W/200X internal engine parts)
"AND ON THE 8TH DAY, GOD CREATED 3 WHEELERS AND HE SAW IT WAS GOOD, SO HE NAMED IT HONDA..."