TRX250R.ORG
Workshop => Engine and Bottom End => Topic started by: sangheraent on June 23, 2014, 08:30:53 PM
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Ok last year I had a motor built by a small dune town shop. I got sucked in by the the talk. The motor is poor power still keeps with a yfz450 but the damn thing is super fuel efficient. The yfz will run out of fuel and I will still have 1/4 tank of fuel left. The bike also runs hot all the time. doing a plug shop shows it nice chocolate brown color and it runs perfectly.
I have never had a 2 stroke be so damn fuel efficient has anyone ever experienced this?
dammit spelt the title wrong.
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Huh, that is actually pretty neat! I'd love that.... For my wife's bike lol. Low power blows, but I am curious what's going on, I go through atleast 2 tanks in the time my 4 stroke friends do. What's your set up? Fuel mix all the way to pipe.
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You say the motor was built but did not say if any porting was done. A simple clean and match will still give the fuel efficiency of a stock motor just a bit more power as all we would like to have. The trx250r was a production motor. Some run better than others out of the jar. My sister and brother in law will not have any port-work done as they like to go out for hours at a time without refueling.
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I bought a 6 pack rack because I thought my bike would chug gas. I couldn't believe it, my bike is a 4mm stroker with a 310 cylinder 72mm bore. The bike should be killing a stock yfz but it is not even winning just keeping up. but man rode for 4 hours on the meter burned only 1 jerry can.
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A ported stock cylinder that can keep up with a yzf450 using less fuel means the porting guy did a good job!
The more efficient the cylinder the less fuel it needs, but just because something is more efficient does not mean its more powerful.
OK I see its a 310, still nothing against you but maybe you are not a great rider.
My nephew (my jockey on my Liger) just got back from the dunes with a bone stock yzf450 and not one stock quad beat him and he only had v shaped razr paddles on it.
I dont think the bike is fast all but the rider is and that could very well be the problem
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This is not a stock cylinder my stock cylinder 261 LRD motor had more power then this one does. This is an LA sleeve 310 cylinder on a 4mm stroker crank. Shoot if my stock cylinder had this much power and used very little fuel it would be great.
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Have you tried givin' er a little more fuel?
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Maybe a little more fuel as it's coming on the pipe would help the power a little.
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I have been riding for a very long time started at 8 I'm 27 now won several mx races and used to drag a banshee for fun. The only reason I can keep up with the stock yfzs is that I have them by a length and a half off the start. I didn't buy a drag motor I bought a motocross motor.
The lack of power shows its face when I'm going up a hill the bike needs to be brought almost down to first and full rev in every gear to do what it should do it 2nd-3rd medium throttle. also my bike will not pull 6th gear.
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is this a spacer plate motor and did they use a spacer plate to try and correct port timing because of the 4 plus crank,Im guessing low compression and lower port timing could cause this
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Maybe the tuning's off or some of the parts your using ain't working together very well. Maybe compression like fearlessfred said?
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My personal feeling is that I got hosed by a builder that doesn't know his stuff and the parts are going against each other. I can't do a compression test for a couple of days but I will test that It runs on 110 doesn't like 100 very much and has decent torque before the pipe.
It is a spacer plate motor I am running brand new reeds Vforce 2s, sparks mx pipe, 39pwk, no air leaks anywhere cr250 ign, "custom cut domes". I am running everything exactly what the builder told me but now he is telling me strokers cant run cr250 ignitions and vf reeds are not good.
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Do you have any other pipes to try?
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now he is telling me strokers cant run cr250 ignitions and vf reeds are not good.
all credibility is lost after that comment LOL. i would have someone credible check your port timings, something is off for sure.
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Lol, aye aye aye... I'd get a refund. That's just poor.