Hey 2-Strokers! Whilst I usually only lurk over here, I had a question for ya'all. 125GP chassis size If you measure the width from frame rail to frame rail up front, how much space are we talking? Or, in short, how large of an area do they have for the engine? Just wondering. Everyone talks about using 250GP chassis for Frankenmoto projects. I love the way 125's rail through corners and therefore got to wondering about using a 125 chassis for a Frankenmoto. There's probably a million reasons why this isn't done. Not knowing any of them, I figured it wouldn't hurt to ask those who know. Yeah, I'm procrastinating at work today. Thanks! - Erik
There aren’t many motors that are going to be thinner or shorter then a 2 stroke 125cc. I don’t know how wide the frame is, but you won’t be able to easily drop in a CRF450 motor ( I know that’s what your thinking).
Hahahaha! Nope, I am pretty sure even without the numbers that a 400cc ain't gonna work. I was actually thinkin more along the lines of one of the new screamin' 250 4 strokes. As of '96, the XR250R measured: 14.5" long 11.8" wide 17.3" tall The new Yammie 250's look really nice, too. I haven't been able to dig up the measurements on them yet, though.
If you'll e-mail me at [email protected] while I still have the TZ in the shop, I can make specific measurements on the '95 RS and the '95 TZ for you. I have some time off for a while and am waiting on two guys to come up with the money for the TZ. Both say they definitely want it, one is selling a car for the money, the other a bike. While I still have it, won't hurt to take a few measurements. I'll work with you via e-mail on it. I was into thumpers, but those things are sorta fragile on the big tracks. My SRX never fragged, but I was always vibrating crap off of it. I really, really do prefer two strokes. Just did an XR80 top end for a friend. I hate having a cam in the way, LOL. Jack
Just e-m me with specific measurements you want done. I'll be out in the shop tomorrow and can measure things.
Hey Jack, Have you heard of anyone putting a RS125 motor in a TZ frame? I have a couple of local kart racers who say that they can make a RS motor fly!
I'd thought of that thinking it'd be maybe cheaper to find a RS motor and the fact that the TZ chassis is well set up. But, looking around, it was as cheap to buy a bike as to buy a motor and hope I could shoe horn it in. Little stuff like the countershaft sprocket lining up with the rear is essential. So many things have to be worked around when you take on something like that even though on the surface it sounds easy. So, I finally sold the SRX for a grand and figure the TZ is worth $2250. I gave $3200 for the RS so it's pretty much a two for one swap. I know the RSs handle well, I've followed too many of them through corners, so I think it'll work out. Jack
Here's some rough measurements of the '95 RS chassis I sent to Eirik. Now, the 94 chassis is different, for sure. The RS has more room than the TZ, over 7" wide between the rails. The '95 TZ starts out at only 4 1/4 inches wide and tapers to about six at the swingarm. Not a lot of room in there for a four stroke cylinder head, but a CR500 might fit. The CR thing would be wild to ride, I'll bet. '95 Honda RS- Frame expands directly behind the steering head to 7 3/8 inches. Front motor mount is 11 1/2 inches below the tank and 11 inches in front of and about 2 1/2 inches below center line of the top rear mount. The lower rear motor mount is 5 1/2 inches wide, the top rear 5 1/4". Lower rear is 6 3/4 inches below the upper rear mount. Countershaft sprocket centerline is 3/4" from the left frame rail.
Hmm, seemed to have left out the inside width across the front motor mount. If you want that, I'll go measure it.
