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Discussion Starter #1
well guys...i had an idea get thrown into file 13 today. in another thread i mentioned putting an RZ350 motor in the new kawasaki ninja 250 (ex250) chassis. sure, that is all well and good. then i went a bit off the deep end. i found a kawasaki H1 motor (500cc two stroke triple cylinder) going on flea bay pretty cheap and close. i thought...ULTIMATE BEAST!! when i called my cousin to ask him about it...WHAM...shot to the floor. he didnt like the idea of 80 or so horsepower going into a chassis build to handle a bike with 36 horsepower. i assured him that the new 250 chassis had to be lightyears ahead of the 1972 chassis (which even sucked in its day) but he wasn't buying it. mentioning cracked motor mounts and possible main frame failure finally scared me away...but what an idea it was! in that lecture he also cautioned me as to how wide the triple was and that it may not even look good in the chassis. he also said "tyler, yamaha and carruthers thought putting a TZ750 in a dirt track chassis was a good idea too...then kenny roberts said he didnt get paid enough to ride it". i guess i didnt need to build another bike yet anyway. thought i would share the idea though, if anybody else here wants to take that and run with it, well, i'll just be jealous of you forever. i still might do the RZ concept though
 

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A new,redesigned 2008 Ninja 250 would be killer with a built RZ/Banshee set-up.
I wouldn't mind having one myself.

A FZR400 with the same power plant would be unique,but the gains wouldn't be as much,maybe a little less weight,but maybe less torque also. I'd rather see H2 engine in an FZR400,but there's something..uh...dirty about mixing brands(even though I like Tritons!)
 

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That Ninja just shows that it is hard to do something that has not been done before. Your idea sounded cool and I would not have thought that it had been done before.
 

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Discussion Starter #5
well, for the moment guys, the idea is forgotten. i missed the bid on the motor, so i will just have to put this back in file 13. besides, i have 2 trucks to finish, a bobber to build, and i want to give pro racing 1 more shot before i get much older. i can always come back to this idea later when i have some more time. have you seen what the 08 250's are going for? used ones with 1,000 miles are going for 600-800 OVER MSRP!! thanks for the link, i'll check that out
 

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i sold a new one cheap at $4300 to a guy three hours away. and it wasn't even at my store he had to pay me then drive another 45 minutes to our other store to actually get the bike. $800 over retail and it still made less profit than a Yamaha VStar 650. AND he could have had a gs500f for pretty much the same price.

also about half of the 250's we have sold were wrecked almost immediatly. (one within hours)
 

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actually all the ones locally were wrecked, and those are the only ones we really get feedback from. so who knows, can you you imagine the horde of ninja 250 carcass's available in a few years.
 

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On the USA 2stroke forum there's a guy that put a RD motor in a EX250 frame. Looks like it belongs there.

I'm in the process of putting a RZ engine in a RD frame. Why? Because the RZ frame is bent and I have a few RD frames...
 

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it takes a powerful lot of doing to get 80 horses out of a H1

and much less doing to make one that puts out a very respectable 40 horses while being very torquey for a mere 30 inches

and 80 horse H1's aren't even remotely streetable

the first year H1's were just about non-steetable at 60 crank horses

the throttle on them was like a light switch making under 20 horses below 6000 and then BAM 60 horses from there up but only thru a very narrow powerband


the later ones were quite mild by comparison

it is easy enough to tune one even softer

so I don't get why your idea was shot down

and I seriously doubt you bought an 80 horse H1

even if measured at the crank

oh now I see you didn't buy it at all

and I'm mad at you for getting me all this riled up with your original post only to then pull the rug out from under me

have you no shame?
 

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tell your cousin that he is so full of shit, and then never ask him again for advice on bikes.

Jeff on the triples board put a triple motor into a ninja frame (h2 I think), and there was a member who did the swap and took the bike to bonneville for LSR

http://kawasakitriplesworldwide.com...days=0&postorder=asc&highlight=ninja&start=30

one that uses a 1987 zx600 frame:
http://kawasakitriplesworldwide.com...days=0&postorder=asc&highlight=ninja&start=60

same bike with an h1 motor
http://kawasakitriplesworldwide.com/phpBB2/viewtopic.php?t=15904&highlight=ninja

Leo overseas has a zx400r with a pretty wild h2 motor in it. thing handles like it is on rails.


suzuki dave on the sundial board has a buffalo motor stuffed in, I think, a cbr chassis.
 

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is this the same cousin that has you convinced your RD chopper is actually a cafe racer?

just asking is all
 

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tyler, let's talk about your choice in engine and chassis swaps for a second....

The rz350 chassis is a pretty good chassis. I mean it is just as good if not better than the ex250 chassis you were considering, so I can't understand your logic in stuffing an rz350 motor in that chassis. Everything you could do with an rz350 in an ex350 chassis you could do better with just a plain old rz350.

now the H1 500, made between 59 and 63 hp (at the crank) and had an awful chassis. Anything you put that motor in is going to be way better than what it had originally (although to be fair the later triples handeled ok, espically the 76 KH500).

there are really only a couple of good reasons to do a motor swap:

- build something that wouldn't normally be allowed on the street. Bikes that fall under this heading are street going 2 stroke gp replicas, 2 strokes with modern suspensions or overall chassis, dirtbike thumpers in streetbike frames, etc

- To give an added hp boost to an already classic chassis while maintaining classic styling. RZ350 eignies into rd frames, h2 and h1 motors into s1,s2,s3 frames, fzr600 motor into an h1 frame (I've seen it), cbr motor into a cb750 SOHC frame, those replica Ducati SS750s with modern monster powerplants...well you get the idea

- To give improved handeling to an ancient engine. Stuffing vincent motor into a modern sport bike chassis, h1s and h2s into ninja/gskr/zx chassis, etc...

Thsi last catagory has some caveats though. As near as I can tell there is no reason to stuff a SOHC cb750 motor into a cbr600 chassis unless there is some racing class that gives you an incentive (in this case it would be LSR since there are classes based solely around engines). There really are no rules to this stuff but it has to make some kind of sense - otherwise you could end up with a bike that is slower and worse handeling than its original two donors (in this case I am thinking a cb750 motor into an ex250 or 500 chassis, where the ex250s power to weight ratio is better than that of the cb750 and that heavy lump in the ex chassis will throw the weight bias off).

I guess what I am trying to say is just being different is not enough, being different and well thought out is the key to a successful combination. Asking people who have expirence with the bikes you are considering is only one part of research and really only a small part, really your research shoudl involve a bike junkyard, a tape measure and some calipers, and a lot of notes. I researched suspension components for a year before I did the fzr400 swingarm on my h1 and now lots of custom guys use it on their bikes.

guys like your cousin are probably very smart in what ever narrow field they work in (sounds like bikes) but they don't know it all and secondhand knowledge is can sometimes be as usefull as a fart in a stiff breeze, espically when that advice is just a mantra against doing it.
 

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I've owned many of the H1 triples, including a 69 model, and the later ones may have made 53 at the crank but nothing close to that got to the back tire

the post 70 versions were all tuned like a farm implement compared to the 69

don't recall ever riding one of the 76's
 

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Discussion Starter #14
yeah i mean, that is why i posted up here, i just wanted to toss things out there, and see if you guys had any knowledge. Thank God you did. I highly doubted that those triples had 80hp from the factory, but i didn't say much. i know that people have built H2's to like 105hp or so, so i was guessing a little on the HP range. After putting some miles on my RD i have realized that i don't really want to do this project anyway. sure it would be cool, but my 40 or so horses of two stroke power is plenty to get me in trouble and i'm sure after i buy a modern bike, i won't want to go through the money and time to build something that is slower and wierd and has to be troubleshot when i have a TRUE vintage bike already and a modern bike. I'll let somebody else fool with the headaches that comes with being a pioneer!! thanks for the opinions guys!
 

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Kaw triples are the balls. they rip on top, they look cool, they sound cool, they are durable. don't got me wrong rd's are great but there is nothing like the trip. less than stellar handlers but a blast to ride none the less. the next time your cousin throws a wet towel on your triple party, ask him if his uterus is flaring up (no offense to go).
cheers, bcr
 

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quote:Originally posted by HackAsaw

I've owned many of the H1 triples, including a 69 model, and the later ones may have made 53 at the crank but nothing close to that got to the back tire

the post 70 versions were all tuned like a farm implement compared to the 69

don't recall ever riding one of the 76's
Yeah it is the same thing with cb750s...rated at 58 for the mid year models but if you see 52 at the rear wheel you have a good running one.

The 76 is the best H1 500 IMHO. I have one that was my bracket drag sled for a while and I am putting her back on the street now. An interesting thing about the h1's is that the 1973-1976 frames are actually stronger than the h2 frames from 72-75. The 73 is the only year where the h1 and h2 used the same CDI electrical components so if you want to do an h2/h1 a 73 makes it a bolt on deal. Post 1973 all H1's have rubber mounted engines, which makes them much better to ride for long distances on, still vibrates like a magic fingers bed but you go numb a lot slower. On H2s you can convert them to rubber mounts with some creative machine work and buffalo silent blocks but to me that kinda kills the raw edge an h2 has. Nothing like feeling all 72hp of paint mixer from your fingernails to your toe nails.

I think Kawasaki had plans to continue porduction of the H1 past 76 and that is why they made a whole bunch of one year only improvements to it. I have heard of 77 KH500s in other markets (Japan?) but I have yet to see one.

Some of the changes include:

- Conventional shift pattern. H1's normally have neutral on the bottom for a N12345 shift pattern. The KH500 has 1N2345 shift pattern.

- Braced frame. By far the best improvement. Kawasaki took a page from the racers who were bracing their frames and did it from the factory. With a 140 sized slick and a braced swingarm I got zero flex under a hard launch.

- Thicker forks. Stock h1's have 35mm forks, the KH500 actually has the h2's 36mm forks and a hub that uses the same brake disc bolt pattern as a kz650 (I think most of the late h1s are like this but the KH only has the thicker forks).

I can't think of the other changes off the top of my head but I believe there may have been porting changes as well. KH500s are kinda rare so if you find one hold on to it - the best frame to use to build a triple based cafe bike.

right now my kh500 has a great motor but I have a 74 h2 mill and a 73 h1 electronics kit for just in case she lets go.
 

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Discussion Starter #19
im lost...what does that have to do with a 2 stroke?
 

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Discussion Starter #20
im lost...what does that have to do with a 2 stroke?
 
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