Got no powerband

[250rsforlife]

I just redid my 250r adding a 310kit an now when I ride I can't get in the powerband and I'm almost positive it's the jets an was wondering what size I should get to make it better so if ya can help me out that'd b great thanks in advance

[sangheraent]

I got some extra, 5 shipped? sorry I had to

[250rsforlife]

I'll take it hahaha

[C-LEIGH RACING]

Need more info, like how much compression the engine has now, what size jets in the carb now, what you set the plug gap at now.
Neil

[250rsforlife]

It's a 150 jet don't know te gap or compression yet but I'll figure that out tomrrw cuz I don't have the tools at home

[Motofool250r]

first what carb do you have?

and second a 310 with a 150 main seems very small what pilot and what needle you using?

[250rsforlife]

It's a kehin carb an yea I know it seems small when I put on the 310 kit I didn't even think of changing it so I was wondering what size I should get

[Motofool250r]

what does your plug look like to me id think your about 5 jet sizes too small.

id say get up into the 160 165 range

[250rsforlife]

Well I ordered a 175 last night so if that don't work I'll try some around the 160-165 range thanks for the help

[Motofool250r]

your local shop should have them, if not try couple carb places online they are not expensive shipping cost more then the jets usually

[250rsforlife]

Yea I think for the four I got they were 8 bucks I'm not worried bout it it's just the time it'll take for it to get here

[beerock]

you need to change your pilot and needle to get it tuned all around

i run a 52 pilot with a 330 dgh needle 178 main

also depends wha pipe you have and what size is your keihn carb?

im running a 39mm keihn and a CS tt pipe

[250rsforlife]

Alright so I tried a 175 still didn't work then backe it down to a 165 it'll kick more in the higher gears but low gears like 1 an 2 there's nothin so what do I need to change to get it runnin in the power band in those lower gears an I'm runnin an fmf pipe

[beerock]

u need to check your compresion

[250rsforlife]

I think it's good cuz it fires first kick with the choke my dad thinks its gettin to much fuel so Idk anymore so I thought I'd come so what u guys think

[250rsforlife]

So I changed my pilot jet to a 60 an a 168 main is this to big or what's my problem cuz its still like bogged down when I try to get in the power band

[beerock]

check your compression

[JackBrown1988]

New to the site, my 310 runs 52 & 178., dgh 3 rd grove.

[250rsforlife]

Alright thanks I'll try that

[250rsforlife]

Originally posted by JackBrown1988
New to the site, my 310 runs 52 & 178., dgh 3 rd grove.
I run the fourth groove an what does dgh mean

[beerock]

was this a new top end or used?

if new how did you break it in?

two people(me and celeigh) with Major knowledge of these motors are telling you to test your compression and your ignoring it because your dad is telling you its ok....

the next thing we do is check cylinder with a dial bore gauge and measure the piston as well. and then the ring gap I forget what the gap between the piston and cylinder are suppose to be...

I had a 250r motor that started right up and had a dead spot in the power band form low to mid high and then would PULL.... the motor was raced in a harescramble and i sucked water in... it wore the rings out and thus made the dead spot... as well as a real weak top end pull

I also had a cr125 that had a worn out top end and had no powerband at all.

if you put this 310 kit in the first thing your suppose to do is check the compression to determine your octane of gas if you modified it or just dont know and you dont know. your chasing a ghost this way...


for a 310 a 52 pilot works and any needle has no effect on top end power band with the mains you brought up WOULD HAVE A POWERBAND if everything else is good...

[250rsforlife]

i bought it new from esr an i wasnt ignoring u guys i just kept forgetting to bring home the compression tester so i was trying to think of what other things it might be if the compression was fine but anyways what is the compression supposed to be an i know u two know ur **** an im glad ya helped so can u tell me what the compression should b on a new 310 kitanill prolly have the tool later tonight

[beerock]

Cal esr for the compression....


how did you break in the motor??????

and what jets were in this motor when you first started riding it?

[250rsforlife]

None of that matters now I think I figured out the problem before I put the kit on I had the bottom end rebuilt they put a short rod in it instead of a long rod an me bein a dumbass didn't think much bout it put the spacer plate they give on an that's what's causing my problem I'm almost positive that's what it is

[Nac's22]

I had a motor that did the same thing and that was the problem. Was an 88 bottom end but it turned out the guy I bought it from put an 86 crank and rod in it. Took the plate off and the motor was perfect.

[250rsforlife]

Yea I feel so dumb cuz it's takin me 2 weeks or more to figure somethin that simple out

[250rsforlife]

Ok so takin the plate out fixed the problem definatley an now my question is should I go back to the jets that were in it or what should I run cuz I have a 60 pilot an 175 main an it still won't hit just perfect at the top couple gears

[beerock]

60 pilot is way too much try a 52 pilot try a 178 main or 180 those jets are close but I don't know what port work is done what carb and what ignition

[250rsforlife]

It's a stock carb I'm pretty sure an the port job is the trx 11 I think it's the one from esr that's for TT racers an dune riders I can't remember the exact name for it tho

[beerock]

Get. 39mm keihn or bikini

[250rsforlife]

So get the 39mm an run the 52 pilot with a 178 main an which side of the carb am I supposed to measure to get the size just so I can b sure its a stock carb

[beerock]

What do u mean which side of the carb to measure??

[87TRX310R]

I'm enjoying this thread:D but to anwser your question. The carb size is measured at the venturi (near the slide) which will be somewhat smaller than the outlet on the engine side.

[250rsforlife]

Well I didn't know an I had a kid at school tell me I'm supposed to measure a side an I didnt exactly bieleve him so I thought I'd ask here haha an thanks

[300exBorg]

You should step back n really listen to what these more knowledgeable people have to say....... just saying

[250rsforlife]

I have an I kinda figured out my own problem an they did give me good info an I was thankful for it cuz I have listened

[JAG Motosports]

actually u could have found the problem a month ago when the 4th post told u to check your compression

[C-LEIGH RACING]

When it comes to any 2 stroke engine performing like it should, compression is the most important thing.
It is as well a tattle tail, by checking the compression from time to time to check the condition of the engine.
Once you see a drop in compression & then check it some time later & it has dropped some more, you'll know a rebuild is soon to follow.
A 2 stroke engine in good shape, will keep a good amount of compression, but things wear & more clearance gets between parts & compression starts to drop.

One way to combat the loss of compression, never run a 2 stroke on the edge of jetting, keep it on the rich side to provide that engine with plenty fuel to lube & cool all the moving parts.
Neil

[250rsforlife]

Alright thanks for the info

[beerock]

Yea c Leigh is spot on hehe it also depends on the kind of gas and oil u run... Unleaded will wear a engine out faster then leaded gas and some oils are superior to others

That's why I run amsoil dominator at 50:1 and vp c12 leaded gas

With that type of setup u can run the motor closer to spot on without worrying about engine wear however not everyone does that and replacing a spark plug every ride or Two is much better then boring and honing a cylinder and buying the next oversize piston to fit...

[250rsforlife]

So how much does the vp fuel cost cuz right now I'm runnin 92 octane from the pump an will it matter if I had the dome set up for pump will it make much difference

[blaster12s]

i just paid 77 for 5gal.

[250rsforlife]

I'll think bout that an alright here's my problem now I run a 180 main an a 52 pilot an it ran kinda crappy for awhile then all of the sudden it hit perfect well I shut it off came inside for prolly 5 minutes then went out an tried it again an it went back to runnin like **** an I can't get the 39mm carb yet cuz I'm broke so I'm just tryin to fix it with what I got can ya think of why it would do that to me tho

[beerock]

What reed cage are u running and it sounds like your carb may have crap I'n it??

[250rsforlife]

Its stock reeds like I said I'm to broke to buy anything else cuz I was gonna get reeds an a carb but I'm broke an so just take the carb out an clean it as best I can hope it works is what ur sayin?

[beerock]

Yes clean your carb if u take it apart and everything is clean then ita leading me to think it may be electrical... Get some carb cleaner and a small cup of the carb is dirty pull all the jets out spray into the cup and then put the jets I'n the cup don't put the float bowl I'n there just spray it and wipe it..

[250rsforlife]

yea ill get on that tomrrw an prolly try another spark plug to see if thatll help an thanks for the help

[beerock]

cool let us know

[250rsforlife]

It still ain't runnin just right it's a little better so I think I'm just gonna wait till I get some money to buy the 39mm carb an mess with it then

[beerock]

what did you do to say it still aint running right? was the carb clean? or did you have to clean it? or did you think it was clean and didnt check the jets etc?


trying to buy a carb to solve the problem may not work, you could have a electrical problem.

[250rsforlife]

Well have a carb cleaning machine at work so I took it there an used it then put it in today an tried a new spark plug an its closer but not right I think I'm gonna try a 178 main to see if that fixes it

[Thornfold]

friends pro-x 310 runs 178-52-cel needle, 2 turns out airscrew. need jet help call carlos-he dialed me in over the phone on my bdtm pro-x 370

[beerock]

Originally posted by Thornfold
friends pro-x 310 runs 178-52-cel needle, 2 turns out airscrew. need jet help call carlos-he dialed me in over the phone on my bdtm pro-x 370

you cant dial in a bike if it has electircal issues....


250rforlife if you cleaned your carb and your having this issue and you say it ran good and then you came in and it ran diferent im leaning towards and electrical issue... check your ground wire... take off the wire and clean the area that it grounds tot he frame and reconnect it.... make sure all your connections are tight from your stator and on your coil...

going from a 180 to a 178 will not clear up a break up issue..... you could put a 190 in it and it will run smoooth up top just be rich.... your break up really sounds electrical now....


as long as you cleaned all your jets on your carb and when you put it back together it was like new jets going in then im leaning towards electrical....... or a possible float level that needs to be adjusted...


you may need to pull your flywheel and check the stator ends and pickup and clean them with sandpaper if they have rust on them.... if they are clean then you may have a bad cdi box... or a bad coil


dont waste your money on a carb without figuring out the problem first... I know the stock carbs have some issues but this soudns electrical... if you buy a carb and have the same issue and have no money again well your gonna have to wait till you have more money to fixe the electrical issue...

[250rsforlife]

Alright beerock I'll try the electrical an se what I can find an get back to you thanks for the help

[250rsforlife]

Alright I haven't been back on here to type anything in awhile but I did the electrical stuff an cleaned the carb again it runs perfect after about five minutes of tryin to get it to run right it's like it had to cough out the problem or something idk so I thought I'd put this on here to see what u guys think

[beerock]

cool

[250rsforlife]

Alright so nevermind it runs even worse it cuts out as soon as I try to give it gas in 6 an only hits the powerband half the time it runs

[beerock]

check your grounds and clean the grounding areas try it again...

you may have a bad cdi try swapping them too

[250rsforlife]

Alright I'll try the grounds again an if that don't work I'll get a new cdi box

[beerock]

I wouldnt buy a new cdi box, you rbetter off swapping one for a friends to make sure thats it.. as well as the coil.... otherwise youll just be buying new stuff(if you can still buy it new) and waste it

figure out whats wrong before buying anything... and if you cant figure it out bring it to someone who can

[250rsforlife]

What other cdi boxes work on it cuz I'm the only one in my area with a 250r that I know of so what other ones can I put on there

[beerock]

you have to get the same year cdi box

[250rsforlife]

Didnt know that but thanks an it's to bad I sold my 87 250x