help with 250r

[ESR250R]

well i pulled my quad down from my truck today hoping to have a good day of riding, but after about 5 minutes i realized that my day of riding was ruined. well anyway to make a long story short, my piston is screwed. i normally run a 152 main jet and it is rich with the box on, i decided to take it off and go for a spin to see if it had anymore power than normal (which it did) but anyway i was letting off the gas in 4th and suddenly my engine died. i kicked it over and it didnt start. we checked for spark and fuel and had that. it still had compression so i didnt think it was my topend. but after a long day and after me ripping the cylinder apart i realized that it was the piston. while i had my cylinder apart i realized that it was ported. i would like for it to be ported for bottom end power, but i am sure that its ported for top end already. i also found out that the ends of my reeds have some chips on them. so i have a bunch of questions to ask u guys and i need alot of different and accurate opinions.

1. who should i send my cylinder off to, to have it bored over and checked for porting?

2. what kind of piston should i purchase, and who should i purchase it from?

3. what can i use to strip the powdercoating off the cylinder?

4. what kind of reads do u guys use and which offer the best performance?

5. is there anyway that they can tell what its been ported for (low end, mid, or top end)?

6. what kind of wait am i looking at? i was supposed to race this saturday and sunday but i dont think thats happening.

7. what kind of cool head do u guys recommend, where did u purchase it from and how much performance did it add to your R?

8. how much do u guys think it should cost to get a new piston, rings, circlip, bearing, gaskets, cool head, boring and possible porting?

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[ESR250R]

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[CBW]

sorry man,,,,i am by no means an expert in who to have R work done by......but this is what i have done on my R's at one time or another.........

Cylinder work,,,,,,,,,i have no idea. On my 85R i bought a new cylinder already ported for MX from nacs when they were offering that......on our 86 R i just put in a 20 over boost ported piston from nacs.....and it runs good for my wife with stock porting:p

the 86 cylinder should just be paint,,,,,unless someone before you had it coated,,,,,,,but aircraft coating remover will take it off.....you may have to work at it if it is really powder,,,,,but it will come off


In my 85 i have FMF torque reeds,,,,,,in the 86R we have fmf carbon fiver reeds,,,,and in my 88R i have boysen dual stage carbon reeds. If i had it to do over i would get a V-Force block and reed setup

As far as the wait goes,,,,,,it may be a week or a month,,,,,,it will depend on the vendor you choose. I ordered a 310 kit from ESR. They said it was in stock...........BUT they forgot to tell me the cylinders were out of stock .......so it may be another week,,,,,,so that is two weeks....for a "instock item"

on the 85 and 86 we have prodesign cool heads,,,,,,,they work well but i have no idea as to how much performance it really gave. My 310 will have a ESR head

cool head will be about 200??? or so......piston, rings, circlips, wrist pin, and needle bearing could be around 100 or so......depends on where you get it,,,,,,,,i would get a boost ported piston from nacs, ,,,,,,i like them......many will have opnions on this i imagine. but you could get it from K&K, or CT,,,,,,just look through the mags on the end table;)......as far as porting,,,,,,look at about 350 to 400??? i am guessing here but i think that is what i saw advertised.

Best info i can give after typing all this.......looks through the mags,,,,,,find some PH#s and start calling.

One of my favorites is ESR and LRD. They may have a 250 cylinder in stock that is already ported............ :confused: you never know..........

just my 2 cents;)

[ESR250R]

thanks for the help chris. i guess noone else on the site actually wants to help someone out with a actually technical question. they would rather go post about how cool nausty's wanna be heel clickers are. hey thanks for all the help guys maybe i should try the connection maybe they would be more helpful.

[CBW]

Originally posted by ESR250R
thanks for the help chris. i guess noone else on the site actually wants to help someone out with a actually technical question. they would rather go post about how cool nausty's wanna be heel clickers are. hey thanks for all the help guys maybe i should try the connection maybe they would be more helpful.


well i tried,,,,,,,,,,,,


when i had r motor problems,,,,,,there was no site to get on,,,or i didnt know about it anyway............


so i turned to the magazines and the advertisers in there,,,,,,,,,,,,,,

sorry man

CW

[beerock]

buy a nix pro x piston, they work well.....

the best reed setup by far is the cr250 reed cage and reeds...

sending your cylinder out for porting is great but asking who to get it done by i slike saying which football team is the best, youll get biased answers.

I know B+b will port a cylinder any way you want for 250-275 thats who did my porting and I have smoked curtis sparks motors before..

B+b ask for butch: 302.836.2012

B=B will tell you to use your stock head- they may even ask you to send it out with the cylinder..(they shaved my head)

hope this helps.

oh by the way, I beleive the boost ports on the pistons is a mythical HP boost, I actually think it makes the piston more prone to breaking..

[holeshot19]

looks like it leaned out on the exaust side. most companys wont touch a cly that has been ported by someone else. and far as pistons pro x are made close as stock. stock pistons are cast and doesnt requre a warm up time. but most pistons like wisco are forged. they are lighter and stronger but doesnt seem to last as long. on my duncan power valve they sugest me replace it every 20 hours of raceing.but on the other r engines i use a boysen rad valve they work great and the intake is made on to it

[Evan]

your name says it all, send it to ESR it will be worth your trouble. I dont know if running lean would have caused that much damage but I dont know. Send it to ESR they are really helpfull.

[ESR250R]

too late the choice was between esr and lrd and when i called lrd they were really helpful and curdious. i have decided on the niks piston. but i am still up in the air about weather or not i should do a cool head and if i should get the piston boost ported? the original piston was a boost ported pro x piston and that motor really ripped.

I may be willing to sell this ..for right price ...its ported for
bottom end & evrythin is brand new ..(cylinder machined like 2 months ago..)
pm me or email ..if ya are interested..