Mugen 360?? The Mystery Is Solved!!!

[1upfront]

What I thought was a 300r kit arrived today and I was comparing it to another practically new one, well I not only discovered that the cyl was NOS like the seller said but also was 80mm and shaped slightly different than the 300 also it doesn't fit all the way down on a bottom end I have down in the basement, I measured how thick the sleeve was and compared it to the new 300r kit its the same but the bore is 4mm's bigger and 2mm's bigger than the FL350 cyl I have I think it's a mugen for the 81-82 250r:D :D
The only thing that sucks is someone bead blasted most of the tomato red paint off.
Heres some pick's.
http://i39.photobucket.com/albums/e183/lrdunlap/100_0230.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0231.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0232.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0233.jpg

[evand]

i dont know anything about airfoolers, but i would buy one just to put that top end on!!!


did you get the piston 2?

[1upfront]

More pic's
http://i39.photobucket.com/albums/e183/lrdunlap/100_0234.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0235.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0236.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0239.jpg

[1upfront]

i dont know anything about airfoolers, but i would buy one just to put that top end on!!!


did you get the piston 2?

No but I found fl 350 pistons up to 82mm's that will work perfect but it came with a 300r head so I think I'll shelf it for a while and look for a matching head.

[evand]

yeah with a bore that much bigger you would have head to jug sealing problems, or maybe clearence problems.

would a dg head work? or maybe get a dg dome re-sized to work with that big of a bore?

i rlly dont know that is just a cool set up and i want to see it in action lol:beer

[Brockey]

I read an article on the mugen 360 kit before. I believe someone here had a link to it.

[1upfront]

The only problem is the dg head is for the stock 6 stud cylinder but this and the hondaline 300 kit have 7 stud cylinders.

[evand]

ooo i didnt know that. good luck with it man, def. a awsome kit

[Louis Mielke]

That head could be reworked to fit. I bet that cylinder would work great with the cases bored.

[1upfront]

Yep but it doesn't have the same contour on the fins also it's obvious the cases will need bored i just set it on the motor to show how large the sleeve is.

[Daddio]

After checking this cylinder out it is clear that it has never been used. It is also not the same bore size that the mugen 360 is advertised as being. This one is 80 mm. Also the pictures that I have seen of the mugens show them having 6 head studs not seven. The nice thing about this cylinder is that the fl 350 pistons from wiseco will fit it perfectly. I just wonder what it really is and who made it. When I calculated the cc's with the air cooled stroke it comes out to 323 cc. Definately not 360 cc and not 300 cc. :wondering

[Billy Golightly]

Honda normally calculates CCs by last bore. For example the CR500 is 491cc on stock bore, but at the end of their oversize pistons its right at 500 if I recall. With Wiseco overbore pistons you can get to 513cc. That appears to me to be a 360 cylinder, and you got extremely lucky. I wanna see that sucker run!

[thefox]

Interesting. I bet finding a head won't be easy unless someone here is sitting on one. did you sheach here yet? Doesn't Bigbore have one on his R?

http://www.3wheelerworldforums.com/showthread.php?t=42823
http://www.3wheelerworldforums.com/attachment.php?attachmentid=18859&d=1131428978

http://www.3wheelerworldforums.com/showthread.php?t=42562&highlight=mugen

[cr480r]

Do you have any heads that share the same stud pattern? If so, just have one re-chambered to fit your needs

[money89tractors]

SO IT WAS YOU!!!! >:P beat me at auction

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&sspagename=STRK%3AMEBTOX%3AIT&viewitem=&item=170190839866&_trksid=p3984.cTODAY.m238.lVI

:D nice buy....

-Phil

[Billy Golightly]

Wow, I bet mikefromlongisland is kicking himself in the ass now :lol:

[Bigbore]

It's not a Mugen. Mugen has a 83.5 mm stock bore and 6 studs.

Looks like a FL.

[1upfront]

Not sure exactly what it is yet but it's in good hands Mike, thanks!

[Bigbore]

Not sure how the 300R head fits? Maybe the FL and the 300R heads are interchangeable? The OEM 300R is a seven stud. I thought the FL was a seven stud head. I had someone tell me that a FL350 top-end would fit on the 250R cases but the skirts wouldn't let it sit in. That the cases need to be machined slightly to allow it to fit. I'd bet that's what that cylinder is. If so That would be a nice bigbore to the 300R kit. Almost close to a Mugen cc's without the price.

Something else... The Mugen kit requires the crank to be drilled to compensate for the heavier piston, that one would need to be balanced also.

I do know that if the 300R head fits on that cylinder, it's not a Mugen. The Mugen also has a head stay on the head and the 300R's don't.

Here is a photo of a Mugen I just took. I just noticed on the Mugen it has "Mugen" cast into it.

[1upfront]

Thats interesting bigbore I've seen plenty of 360 kit's for the cr in pictures but never a 3 wheeler one till now thanks for posting the pics. Wonder who made this cylinder then I know it's not an odyssey or hondaline 300 kit:wondering :wondering
Here it is compared to an FL350 cylinder.
http://i39.photobucket.com/albums/e183/lrdunlap/100_0240.jpg
http://i39.photobucket.com/albums/e183/lrdunlap/100_0241.jpg

[Daddio]

Another thing that this cylinder has that the mugen didn't have was a cast sleeve. The mugens had chrome cylinder walls. It also isn't an odyssey cylinder he already has a couple of those. One will be going on one of his next projects. This is actually bigger than the odyssey bore wise. The porting in this cylinder is very similar t o the 300 hondaline cylinders. This cylinder was red originally like the 81-82 Rs. I guess it is the mystery cylinder for now.:wondering

[Daddio]

Well after several days of research I came up with nothing so I pmed Mike Coe. Here was his reply.
Re: 250r question
Daddio,

You may have stumbled across a very rare top end that was only available to Team Honda directly from Japan. We were sent Team specific 350cc engine package from Japan. If the cylinder you have is in fact one of those, you have scored!

You should measure the height of the cylinder. You may find that it is a bit longer than the 300 cylinder. This is because part of the 350 kit was also a crankshaft with a little longer stroke to complete the 350cc package.

We race tested a number of of the 350cc "kits" in open class competition with excellent results! Ultimately Honda decided that a "bolt-on" kit would be a better seller due to ease of installation, hence the well known 300cc kits.

Did the head also come with the cylinder? Since it appears you have a number of similar parts such as the 300 cylinder and the idiossy cylinder, you could use one of those haeds and modify it to work as I believe they all shared the same bolt pattern and spacing.

You would then need to see if you can score the proper crankshaft or at minimum have a stock 250 crank stroked to 69 or 70 mm to complete your
350cc kit. Once again, nice find! Keep digging, you may be able to uncover the rest of the parts!

I think the counter balancer was also a bit different as well and also came from Japan with the rest of the 350cc parts. If you can't find those parts I feel you will still find the 350 kit worthwhile to have 250 parts modified to complete the conversion.

Honda Japan also sent water cooled top-end parts for our 84 model trikes! The parts were also "bolt-on" deals. I personally had all of the brackets and radiators custom made for all of our conversions!

I still have a few of these "kits" myself and currently have one installed on my original 1981 model
ATC250R racer.

Good luck and ride safely.




I went down to the" Basement"and measured the mystery cylinder and it is 3mm taller than the 300 cylinder. Mystery solved.:naughty: :D

[Twilight]

Nice!!! I have one of those kits on my Honda FL350, its one of those things that Honda never released. 420cc cylinder and head with watercooling on the head and cylinder.

Good find man, if you want. I can ask some of the Honda guys I deal with for some parts you may need.

[Dirtcrasher]

WOW, so Mikey gave up a 350CC NOS cylinder for an air fooler..... SAAAAAWEEEEEEEET!!

Now, get it going beyatch!!

[dizasterzrfun69]

Wow, I bet mikefromlongisland is kicking himself in the ass now :lol:


now he probably is :lol: :lol:

[Daddio]

After I measured the cylinder yesterday I pmed Mike again to thank him and let him know that he was right. Here is his reply.

Re: You were right!!
Daddio,

3 mm taller deck + 3mm down would equal + 6mm stroke. A 70mm stroke when coupled with an 80mm bore will give you 350cc.
You will have to do a bit more research to find out for sure if the Odyssey piston will work. The wrist pin location may not be optimal. But if your luck continues, you may find that it is a perfect match!

There are a number of folks out there that can stroke crankshafts well. As I recall, the ones we had used standard ATC250R rods for ease of rebuilding.

We first got the 350 kits for our 1983 models. All of the air cooled engines are nearly the same, so the parts would work on 1981-1984 models.

The reason for the kits was so Honda would have a "true" open class displacement for open class competition. Back in the eighties some entered incrementally larger (@258cc) engines to compete in the open classes, while some sanctioning bodies required a minimum (@340cc) to be legal for open class.

At the same time, folks were "destroking" 250's to eace against the ATC200X, and WERE ALLOWED!!

That should have never happened, and fortunately a 2 stroke 200cc class was formed. Why? I don't know. It sure seemed like a waste of time and effort.

There was never any "production" 2 stroke 200cc 3 wheelers, but Kawasaki leveraged their destroked
250's to race against the 200X and many canctioning bodies allowed them to compete.

That is why Honda unveiled the unbelievably trick ATC200R model to race in this class. What a fiasco.

Since it wasn't until 1985 that the AMA took control of the ATV racing, there were never any "set" rules until then. Of course the AMA brought along a whole new set of issues regarding ATV racing.....
Oh brother......... Again, what a fiasco.

Good luck with your 350.

Quote:
Originally Posted by Daddio
Mike
You were totally right. I just measured that cylinder against the 300 and it is 3 mm taller.
When we bought this it was just the cylinder and a modified 300 head. I found that an Odyssey piston will fit this cylinder so we are in luck there.
He was planning on building a 250r with an Odyssey cylinder and having the crank stroked to get the 350 ccs so now he will have to start looking for another trike for this engine project.
By the way what year250r did they put these cylinders on?

Thanks again,Ron

[Bigbore]

Better than a Mugen! Good Score!

Now you need to find the rest of it:cry:

[atc300r]

Im posting this kinda like and up date . Heres a pic of what Honda used may have used a 350 cylinder for. And some pics of were this particular cylinder ended up.Stroberts ended up getting it from 1upfront and had it fit onto a second gen 250r.186659. 186660 186661 186662

[manbearpig]

DP, that first photo was taken from my family's photo album. It was taken by my father in 1981 at Riverside Raceway. lots of things happening back in those days, so its not surprising Coe got his dates mixed up.

[6speedthumper]

Really awesome and amazing find! Had no idea that these kits ever existed. Really neat to learn about all these kits, and racing classes. Hope you get it all together!

[atc300r]

Paul, hope you dont mind I used your pic. I think its only 1 of a few that shows the 350r that team honda used. Its awsome that your dad knows these guys and took some awsome pics of trike racing from back then.Theres a couple vids of Stroberts riding and a walk around of it. I will get a pic of the completed bike. Looks awsome finished he did a great job on it. He also has a 300r and 360 first gens he did.Plus a few other trikes. I came across this post and read about the cylinder on another site thought Id post what became of the cylinder.Shannon built me a plus 3 swingarm for my 81 250r flat track racer.186666 186667
http://airfoolers.com/forum/index.php?topic=5766.100

[Daddio]

Paul, hope you dont mind I used your pic. I think its only 1 of a few that shows the 350r that team honda used. Its awsome that your dad knows these guys and took some awsome pics of trike racing from back then.Theres a couple vids of Stroberts riding and a walk around of it. I will get a pic of the completed bike. Looks awsome finished he did a great job on it. He also has a 300r and 360 first gens he did.Plus a few other trikes. I came across this post and new read about the cylinder on another site thought Id post what became of the cylinder.Shannon built me a plus 3 swingarm for my 81 250r flat track racer.186666 186667
http://airfoolers.com/forum/index.php?topic=5766.100

WOW!!! An oldie but goodie. Shorty after this thread started, 1upfront, found a Mugen cylinder. He also, after searching high and low, found a matching head and later a piston for it but. Before he could finish it, the bottom fell out where we work. Up until last summer we were both struggling to keep afloat. Neither one of us did much riding or building. That's when he sold the 350 cylinder and head to Shannon. Shannon did an awesome job building that machine along with the others he has built. It definitely went into good hands.
1upfront and I have slowly been getting back into building and riding a little more. He still has the Mugen 360 and I wouldn't be surprised to see it in a machine sometime soon. I'm sticking with my horizontal cylindered Honda's. Right now he is working on a hybrid atc70 and I'm rebuilding a 74 atc70.
It's kinda neat to see this thread resurface after all of this time.