Quad Racer 34

iTrader: (4)

duh i never thought about that. a couple friends that race pro are only getting 7-8 min. one has a jammin just like mine and the other has a ninja. i never thought of it that way oops

thabiuk

iTrader: (2)

Kind of both right, I am in no means a throttle grabber, I come from a TC back ground. At the Farm 2, I was getting 11-12 with about 6-7 tanks on the motor, but again the motor was only getting 3/4 open and tuned to that. If you drive at 3/4 with it tuned to wide open and move the radio end point it will run overly rich until tuned.

At NVR a smaller but tighter track, I found the issue with the thorttle adjusted and retuned and runtime dropped to 7-8 or less. I let my buddy drive it Alex Brimingham and he ran out in a 5 minute qualifier.

NVR has about a 700 foot centerline but tighter turn you sprint and brake to0, not rolling the corner like you would at the Farm. Perhaps that is a bit of the difference.

But I think the insert will bring it back up, I am not good enough to grab full throttle and use all the power the motor has. I think I sould be more worried about runtime and consistency.

Maximo

iTrader: (11)

Geez I can't even imagine running out of fuel at 5 minutes LOL ! I use a 086 on the JPX 21, Picco glowplug and 30% fuel..... we have gone as much as 11 minutes on a tank, made 10 minute pitstops under the right conditions, and under any conditions we can make 8 minute pitstops.....IMO if your running out of fuel at 5 minutes the engine must be tuned extremely rich, or something isn't jiving with the setup....I have drag modded 28's that will go 5 minutes with ease, so a stock 21 should never be out of fuel at 5 minutes...it must be smoking like a freight train !

Quad Racer 34

iTrader: (4)

is the track you run on small? small as in not getting past 3/4 throttle?

BeefHead

Started break in on mine today. The needles are dead on for break in i did not have to tuch them. Just primed heated and started right up.Will run this sat. at pro series race with a msr1005 pipe . I will tell you guys how it goes.

slayyer

iTrader: (29)

i used to run a jammin .21 with a dynamite 053 pipe and got around 7min a tank. i dont run one anymore because it only lasted me 3 gallons and IMO i dont like the powerband. too much bottom end! but instead i got a plus 4 and absolutely love it!

Quad Racer 34

iTrader: (4)

WOW!! you must have gotten a dud or something because ive been told from a lot of people from my local track they have got 10 gallon easily.

Maximo

iTrader: (11)

By no means ...the worst mileage we see is a 8 minute pitstop...on a small track or hard pack we can easily get 10.... Our typical track is a big rack ( 200' straight) with loamy soil which uses more fuel then the typical clay hardpack....We have no issues at all with runtime, but we also are very particular on setting these engines up..Picco plugs only and a 086 pipe..IMO the hotter OS plugs people love to run need more fuel to run properly which kills mileage....It is all in the tuning and setup, jammins usually come with a extra head shim ( which we remove) , increasing efficiency of the burn, we use a 086 which suits the engines powerband, and a cooler Picco plug, which gives a better tune.....We also don't have any issues with getting 8 gallons or more of hard racing out of a engine..we break in on a stand using HPI fuel, then switch to OD after for racing....We also take extra care to make there are no vacuum leaks in the carb as well, which will also hurt mileage...And of course tuning, these engines can be sensitive to tune..knowing how to tune them makes all the difference....

Maximo

iTrader: (11)

Here is a video of a X2 CRT with my stage 1 JPX 21.... this is just some practice laps on a ungroomed track....we were getting eaten alive by mosquitoes so we having difficulties driving.... We shot something like 11 minutes of video and had fuel to spare...

http://www.youtube.com/watch?v=6sk_GTRpa_U

Maximo

iTrader: (11)

Wrong pipe choice for that engine...should have ran a 086 on a Picci plug...would have had less bottom, more top and better runtimes...

Quad Racer 34

iTrader: (4)

yea that track has more twist and turns than the one i run on. that one is a bit bigger but doesnt seem to be on the throttle as much. nice track though. that straight is llooonnnnngggg lol. im going to do more testing this weekend IF we even get to race. i need to lean it a bit more on the lsn. it was probly way too fat to get good runtime. but they are calling for a lot of rain so idk if we'll get to race.

thabiuk

iTrader: (2)

I have heard of people getting 3 or 4 gallons, the cause seems to be premature bearing wear. Using the same bearings as the V-spec, I would think that could be a very definite possibility. I and most everyone I know that have one or are using one, has switched to TKO ceramic bearings.

BeefHead

+1 on the TKOs . My old jpx .21 I installed TKOs at 3 gal. and got many gals. from mine. I dont baby my engines I always have a very crisp race tune.Run time is not bad with these engines. I always get 8+ mins. with these . I have a heavy hand.

JUD

iTrader: (4)

Is this still a Picco based engine? I see the box is different.

Maximo

iTrader: (11)

I have been running Picco's for 3 years now, running them harder then most people ( especially considering many are drag modded ) and we have never had to replace a rear bearing... And this isn't just 1 or two engines, I have had dozens of these pass thru my hands.....There has to be some element of user error involved with all the premature failures as I don't have any of these issues at all.... In fact I think Picco uses very good bearings and based off my experience they last better then most engines bearings do.....