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Discussion Starter #1
Hi guys.

I've got an 87 250r with a ESR 330 PV and an pkw 38mm carb. I've been noticing that at the high end, I'm getting what seems to be a rev limiter. Like the spark cant keep up or something. I've changed the CDI box and cleaned the air filter to make sure the engine can get its air.

I rode a stock 250r this last weekend and noticed that it reved until it wouldn't anymore. It hit a point where the pipe (I assume) wouldn't let the engine rev any further. It was smooth.

My 330R is not like that. It feels like there is an issue. I'm running an ESR TRX5b pipe. I'm wondering if I should replace all my ignition stuff with the CR250 ignition. I don't pretend to be an expert, but I'm trying to learn. From what it seems like... I want the 2001 CR250 ignition system? Stator, flywheel, CDI, coil, etc? Anyone know where the best place to buy that stuff is?

Thanks, John.
 

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the cr ignition is a good upgrade..not saying for sure but the 3 pv motors I have ran sorta did the same thing.i think it's more the cause of the pv closing without the pressure needed at wot.no over rev.might not be the problem but hopefully someone else will chime in.
 

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I have the same issue....ive been searchin high and low. im running a 86 bottomend with long rod/spacerplate and 86 piston and had head milled .010. 39mm carb and CR intake boot.
I had to modify the reed cage to make it work ...I think the reed support backer were hittin on something inside. so I removed them.
motor was rebuilt twice before. its close to its last bore on stock jug

what would the symptoms of bad or weak reeds be?
could it be a squish issue?
 

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I to am having the exact same issue. my set up is exact same as hammerdog. I was wondering if it could be the cdi as well....
 

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I have also tried swapping out cdi, rectifier, stator and coil off a known good running 88250r...
I live in Michigan and the problem happens winter or summer...
if I can remember right it, mine seems to happen after the motor heats up. it been a while since I have ridden...kids...lol
I am having motor rebuilt by a Honda tech this time...
 

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Hi guys.

I've got an 87 250r with a ESR 330 PV and an pkw 38mm carb. I've been noticing that at the high end, I'm getting what seems to be a rev limiter. Like the spark cant keep up or something. I've changed the CDI box and cleaned the air filter to make sure the engine can get its air.

I rode a stock 250r this last weekend and noticed that it reved until it wouldn't anymore. It hit a point where the pipe (I assume) wouldn't let the engine rev any further. It was smooth.

My 330R is not like that. It feels like there is an issue. I'm running an ESR TRX5b pipe. I'm wondering if I should replace all my ignition stuff with the CR250 ignition. I don't pretend to be an expert, but I'm trying to learn. From what it seems like... I want the 2001 CR250 ignition system? Stator, flywheel, CDI, coil, etc? Anyone know where the best place to buy that stuff is?

Thanks, John.
John:

Try adjusting the PV; turn the screw all the way out...if it still does it, go to a larger 'bleed off jet' (the main jet screwed into the PV body) or open up the PV and cut the spring a coil at a time. These 'blade type' PV's are not the best, however; we seem to get them to run good with adjustment.

My biggest concern with the blade PV's is not the lack of performance; it's the relatively high rate of 'blade' failures...keep a good eye on the PV.

Carlos
 

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Discussion Starter #11
John:

Try adjusting the PV; turn the screw all the way out...if it still does it, go to a larger 'bleed off jet' (the main jet screwed into the PV body) or open up the PV and cut the spring a coil at a time. These 'blade type' PV's are not the best, however; we seem to get them to run good with adjustment.

My biggest concern with the blade PV's is not the lack of performance; it's the relatively high rate of 'blade' failures...keep a good eye on the PV.

Carlos
Hey, thanks Carlos. That's what I will do. I know that my PV screw is really far in. I'll pull it all the way back, then try a larger jet, and finally cutting springs if I have to. I appreciate it.
 

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Discussion Starter #12
Well it's been 5 years, I've been off the quad for a long time, and here I am, getting back into it.

Took the top end apart, and everything looks good... This time I know enough to individually check each electrical component against the service manual, and everything checks out, awesome. I was about to buy a new CDI, when I see that 5 years ago I already tried that.

What I did notice was a lot of burned oil on the underside of the piston, and the exhaust side of the piston looked like it got HOT. Wondering if I just always had it too lean, esp in the midrange.

Am running a non-resistor B9 plug as well.... going to switch to an R.

Here's a small album
 

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Burnt Oil under the piston crown, Black, Crusty is a sure sign of a Piston running Hot and possibly Lean.

Carlos
 

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195 Main seems Big relative to the 45 Pilot. While they are different jetting circuits, their is a correlation between them; 195 Main & 52-58 Pilot or 45 Pilot & 160-175 Main.

Something seems way off...

Carlos
 
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