Author Topic: new ESR 310 kits reliability? (Read 4947 times)

jfwyatt1 · « **on:** May 20, 2014, 09:30:23 PM »

we fried the topend last weekend 38 pj has been giving me fits and for some unknown reason leaned out bad on my son and instead of going back with a stock cylinder current cylinder is at 68.5mm i am thinking of just buying a whole kit (cylinder, head, carb, pipe,ect)from esr. and get rid of my current Carb and pipe (38PJ, and Bills pipe). what kind of reliability can i expect compared to stock cylinder setup?

pinned250r · « **Reply #1 on:** May 20, 2014, 09:35:19 PM »

Reliability all depends on maintenance. I have heard the ESR big bores can be picky with temp changes, but again, thats just maintenance that comes with any big bore. Cant beat it for the price!

jfwyatt1 · « **Reply #2 on:** May 20, 2014, 09:42:02 PM »

my biggest reason for leaning this direction is i know i need a new carb as the PJ we have been using is old and worn. the cylinder we have probably will need resleving or panother cylinder and i am not happy with the bills pipe. so the kit from ESR kinda takes care of everything at 1 time. if i go that route i was planning on calling them and maybe talking with eddie and getting his opinion on what specific kit i should go with

pinned250r · « **Reply #3 on:** May 20, 2014, 09:53:01 PM »

Correct, if you need to resleeve, dont do it to a stock cylinder, unless its heavily ported and you love the port work. But yes, calling eddie would probably be the best route.

Sand_Blaster · « **Reply #4 on:** May 20, 2014, 09:57:13 PM »

No issues with my older esr 310 with a ton of hours on it

rablack21 · « **Reply #5 on:** May 21, 2014, 07:53:48 AM »

I have raced my ESR 310 pv for the last year and a half with no issues. I ran it numerous hours just fun riding the 2 years before that. I have not had any problems with it.

Burns363R · « **Reply #6 on:** May 21, 2014, 07:58:00 AM »

There was a rash of issues 3-4 years ago. But i havent heard any issues with ESR cylinder for some time. I think they got something sorted out. Probably a good option for the money.

kb250r · « **Reply #7 on:** May 21, 2014, 07:10:37 PM »

You're in need of a full upgrade you will not find a better deal on a full package deal like from ESR...I would not hesitate to run a full esr setup...

jfwyatt1 · « **Reply #8 on:** May 21, 2014, 08:16:05 PM »

thanks guys for helping me make up my mind now im just waiting on my tax refund from state.

C-Leigh Racing · « **Reply #9 on:** May 22, 2014, 01:02:11 AM »

J,
be sure you get the updated cylinder, with the machining done down in the cooling jacket over the top of the exhaust to promote better cooling.
The ESR heads have been changed, machined with smaller coolant passage way holes at the rear of the head, so that more coolant will flow around the cylinder & then out into the head over the top of the exhaust port.

For the price, you can beat the ESR cylinder kits.
Neil

etccb · « **Reply #10 on:** May 22, 2014, 10:11:36 AM »

As far as the head the esr heads have always had a smaller passage to the intake side vs the ex side. It was others that had the same passage size cut outs front rear on oring heads, not esr.
They also now have that power valve ready option for like $10 to $20 just in case you would like a pv but your just not ready $$ right now. You can drop one in later if you would like with that option.
These are great kits wyatt from a company that has been doing performance work on 250r's from the day they were born, the R that is.