RM 250 Powered Road Race kart

[Rickracer]

Nope, nothing adjustable, and it WAS an asphalt oval track kart before I got it. People always come over look at it at the kart track and the dragstrip. I think I'm gonna be glad I've got those 10" wide wheels with this motor, they didn't let the kart turn very well with the Honda motor on it though, it ran much better with 6x6 tires with that motor. So far I'm likin the 12x8s, if it's not turning hard enough, just add a little more throttle,
I'm gonna start with Maxxis 12x8x6 HT3s on the rear, and 6x6x6 HT3s on the front and see how that does. I've got a line on a quantity of Firestone YJFs for the rear too though, waiting to see how that pans out.

 

[anderkart]

Yeah my kart came to me with 6" diameter rear rims and I kinda like em better than 5"s too. I resently picked up a pair of Burris 11.50" x 800" x 6" (55 compound) that seem to be hooking up really well. I've heard lots of good reports about those Firestone YJF's.

 

[Rickracer]

This is just messin around in the parking lot at the shop, I just put in a little taller geared front sprocket for more top speed and a little less violent reaction to the gas pedal, :mrgreen:







As if you can't tell, this thing is a TON of fun, and could easily be very dangerous.

 

[kazkepox]

looks like someone could use a haircut

 

[Smurph]

Wow. That looks so fun!

 

[Rickracer]

I could almost see myself participating in stunt show with this thing,

 

[Kaptain Krunch]

Holy ****, thats crazy, almost too much power.

 

[Rickracer]

First off, there ain't no such thing as too much power, only not enough traction, , and besides, TOOO MUCH POWER is JUST RIGHT for me,

 

[Rickracer]

Well, I ran an 8.90 @ like73 mph today, and several people told me I pulled BOTH front tires on my first launch,
It felt like it to me too, but I didn't want to say so till somebody else told me,

 

[1992suburban]

was it wide open???

did you notice what gear and rpm you were at coming through the traps???

 

[jr dragster T]

I'd be a little scared if only one front wheel pulled off the ground. Good work on the kart!

 

[Rickracer]

I was about the top of 4th, I THINK, my tach is goin nuts with this motor for some reason. My mag cover AND mag screws fell out coming up the return road after my 2nd pass. I dug around and found the right screws to put them back on, and set the mag where it appeared to have been before but it was idling funny and stalled twice when I was lining up for my third pass, so I put it back on the truck and called it a day as far as running. Don't wanna burn a piston from detonation or anything. Gotta find out how and where to set the timing now and git-r-dun,
I Ran my friend's tri-power SBC powered 1929 Model A Roadster pickup hot rod a few times too,

 

[Rickracer]

My future son-in-law loaned me the manual for his 2000 RM 250 and I figured out how to set the timing, now it's faster than ever. I think the mag plate may have been loose from day one that I've had this motor. I'm thinking about retarding the timing just a bit for less bottom end and more top end,

 

[Lynder2]

sprocket

Hi, I,ve been following your build for a little bit im making a rm125 kart, but i can't figure out where to get a 520 chain sprocket where did you get yours?

 

[Lynder2]

and sprocket hub

 

[Ferrari motors15]

I get my 420 sprocket (26tooth) at General Bearing(GBS) with a 1 inch hub on it for 32$.
They have a lot of sizes so im sure you can find the one that you need.

 

[Rickracer]

I got the one I have at QRC Karts, it's for a 520 chain, 1 1/4" axle hub, 23 tooth sprocket. You need to be aware that MX motors have a primary reduction, (mine is 3:1, probably most will be close to that), and ALSO the 4, 5 or 6 speed trans, so you need to go pretty small with the gear, I'm actually thinking about going to a 20 or 21 tooth axle sprocket.

Here's a link to the sprocket: http://www.qrckarts.com/store/index...&Product_ID=246&CFID=7539090&CFTOKEN=56484040 , I couldn't find the hub on their site, but when I called them, they said they could send it, no problem, worked like a champ,

 

[RB240Mike]

This thing is sooo bad *** but I'm coming for ya Rick! I'm trading my extra frame and extra kt100 for a complete ninja 250 swap including radiator and everthing... now I get to do all my neat things I was telling you about. It should be fun!

 

[modelengineer]

I'm thinking about retarding the timing just a bit for less bottom end and more top end

Advancing the timing should give you more top end

 

[Rickracer]

Advancing the timing should give you more top end

That's possible, I do know that small block Chevys like a few ° of retard at the top end, maybe two strokes don't, but advancing it would definitely give me more bottom end, which I definitely don't need,