RC Nymph

Okay...after reading this post maybe someone can help me out. I have a GRP .21, love the motor! However , I am working on my third gallon of fuel and can't seem to keep it from flaming out. About 2 weeks ago, my carb stuck and we pulled it off, cleaned it, and found a pretty good scratch in it. just picked up a new carb from my sponsor and replaced it. Engine ran good for the first heat, flamed out in the second heat and didn't get to finish. Ran 13 minutes of my 15 minute main, first pit stop went okay...got back around the track and flamed out. then it seemed that we couldn't keep it running. After racing, we played around with it and had the track owner help us out...great racer and pretty knowledgable. After taking 3 laps around the track, it flamed out...brought it in and found out that we were able to turn the flywheel with little to no effort. Let it cool down for a few minutes...started right back up, ran a couple of laps and it flamed out again...with the same issue with the flywheel. We are being told that there is not a lot of compression in the engine, therefore causing the flame outs. I'm rather disappointed since the engine is only 2 1/2 months old and I'm a beginner racer, so I'm not balls out on the throttle. We were told to have it pinched and should be good. Should this be the route to take or just try changing to a #4 (running #6) plug and change the tune. I am lost as well as my husband with this motor. Please help

FrankBlack

Remember they are not a high compression engine, only way to tell if the piston/liner is gone is to pull it out and see where the piston stops in the liner. I think most problems ppl have with this engine, including myself is just mixtures.

RC Nymph

Thanks Frank! I'm going to go with the #4 plug and start changing the needle settings. Right now, I can't even crank it by hand. It has been a power house for me up until lately, but that's also when the temperatures started rising here too. I'll give that a shot before I get it pinched. I love the motor, just had a bad couple of weeks with it lately.

mixedguy

iTrader: (65)

so ordered new plugs 4 and 5 so i shpould be looking for a temp between 190 and like 210 i am in st. louis mo so high humidity. i am new to nirto but hve lots of help at track from big name guy like josh wheilier. everone keeps telling me oppiste of what u all tell me but they dont run grp they run other mills. so i am on a sole mission to get this thing ripping i do understand tuning and want this to be my new motor line. just from what i read in another rc tech post i had this thing screaming top but way to soft bottom. thanks for all the help. just seems so backwards from what i hear about tuning motors but i do what other have tryed with same product and dont argue cuz this is supose to be help not i know it if u all know what i mean

mixedguy

iTrader: (65)

o more i have a ninja bo1a .21 that has same amout of fuel through it and grp is better to me lts rem i am a rookie to nirto and but grp is smother and just feels great even with bottom a lil soft had to adjust driving cuz grp has more power. not sponsored yet not just putting it out there from what i read nothing like that grp is far better and if a rokie that knows a lilttle but not alot can say that i hope it ends alls this comprasions issue. i do have a ? though should i use grp 4and % plugs in ninjia . and one more thing i have jp-4 and grp 2053 wich pipe shhould i use with witch motor?

FrankBlack

Lifted from neobuggy forums:

The info in BradSLC's post seems to back those statements up aswell.