The seller said it's a new rod. I think it ran it a couple times that's it. So new rod, new bearings, and fresh pinch for a great price. If it lasts me 3 gallons it's paid for itself.

I have a new piston,sleeve,rod and wrist pin. What is it worth ?

search for .21 grp on ebay. it still has a few days but there is a nip tuned rod:nod:

Would an OD 97 or 99 work better in a Tuned running 30% in 100 degree weather?

97

I just picked up a used GRP .28 MRT with grp exhuast (2053). I got it for $100 bucks and its not in the bad of shape at all.

Until i thought. I have a really high idle after high speed passes. This is my first GRP so i had to do some research to get the correct needle settings and to read about all the different things people go through. Well the guy i got it from used OS p3 which i found out after is a bad idea. Im assuming the plugs will leak. Would that be the cause of the crazy idle?

When i do a high speed pass. the engine will be revving high then it will go down after 20 seconds or so. then if i just tap the throt it will go right back up.

Well i couldn't figure it out for the longest time and it was about to just be a shelf queen at this point. I really wanted to use this mill. so i picked up new p/s, rod, pin, clips, front and rear bearings. cleaned up the inside put her back together than started her up. Well same problem. I sealed the engine's carb and backplate while it was apart too as i do with all my engines.

I still dont know what is wrong with it, maybe its the plug that im using. i just ordered a new head button so i can run the grp plugs. Im hoping that is what the problem is.

has anyone ever had this problem? If so, what did you do to resolve it.
i just got my untuned grp .21 yesterday. So if i can't fix it, im just going to swap the parts that i can with the .28 and .21.

thanks for all your help guys.

tooo lean on the top

the guy you bought it from used os plugs, what did you use???

i am sick of ppl saying you cant use the os plug, because you can....i have not changed back to grp plugs....i will put one in, and i will bet it wont leak...

the os plugs are fine and about 5 dollars per plug cheaper than the grp plugs....

I'd rather use OS plugs myself. I run them in my OS Speed and love OS plugs, they last so much longer.


i actually had it on the richest setting it would run on and it would still idle like that.

Could it be that im using 20% nitro? i know that these engines come from the factory to run 30%

its driving me crazy. Once i get this untuned broken-in, ill throw the .28 in and give it another chance.

if i used os plugs, am i able to put a grp plug in? I heard that the taper is a lot different from the os. then again you can't always believe what you read these days.

thanks for the replies.

I know this sounds crazy, but I strugguled with the same problems with my MR Ninja (GRP)

The cure:
Lean idlegap and lean LSN propotionally.

Do it.... Dooo it ;)

do you know how many turns out the LSN is? Someone else told me that I had my LSN to rich so it can't burn all the fuel that floods into it.

I'll give it a shot. GRPs are so much different to tune IMO. you have to make the smallest adjustments.

As a general rule i found:
Idle gap - smaller than you'd think
lean bottom - rich on top

www.raceprephobbies.com has four losr2043 rods in stock. I just ordered one. Kinda salty at 62 bucks plus 10 for shipping, but i think its worth it.

allmost forgot; P3 or ODO97t - or a really hot grp plug

I have 2 extra rods right now already. Thanks for the replies. i run the P3 in there already. I was even thinking the P4 at this point. I'll close up that idle and try messing with the LSN tomorrow. It's about to rain here.

I hope i can get this to work!