really? i was just thinking about it because i was told that if u replace them soon after break in u can get atleast 10 gallons for the minimum.

Proper motor care and not running it lean will achieve 10 gallon's.....not using ceramics alone.

Im at the one gallon mark on my Jammin Plus and it showing some real nuts now ! I still have the original plug in, and was wondering how long before I should change my break in plug ? Indoor is starting next week and we will race nitros every other weekend till spring, should be able to give a little feedback on this engine with a little more run time. So far this engine hasn't missed a beat, the bottom end was real lean from the factory settings . I will be replacing my plug with a picco plug, ofna#51006 :)

easy a gallon or 2...if your tune is on they will last and perform like brand new...its THE only plug i recommend for these motor's.

yea i was running mine the other day and the motor keeps getting better and better everytime i run it. i had a real good tune on it on where it was screaming down the straight and coming out of the cornors (and no rich bog on the lsn) and it was barely breaking 200 degrees. i love this motor. i run a 053 pipe with it and on the track i race at you are on the throttle A LOT and i was easily getting 7min.. so the indoor track im racing at in a couple weekends i should probly be pushing 9min hopefully getting close to 10min. i might be able too because its not a big track anyways.

I think I'm going to give this engine a try I have a jpx.28 and it is a great engine I'm running a ninja jx .21 right now in my RC8T and IGT2 . Have any of you guys ran the two engines and can tell me how they compare to each other in power bottom and top

Ill let Max feild that question....i haven't ran a .28 in a while.

I'm sorry I was not clear I was asking to compare the jx.21 to the jpx.21

For the old Jammin 21 I can say for sure with almost any pipe the picco will eat a ninja for lunch up to mid rpm.

From mid top high rpm it depends on pipe but picco will mostly keep up with the ninja & with a cheap thick 086 pipe will feel about even with the ninja.

That is the old jammin 21 compaired the the new ninja at my tracks,the new picco I dont know but ASSUME it would be even better on top as that seems the way they have been going with their motors from the O.G. P7 through the newest versions(less bittom,more top)

We will have to ask Maximo if there has been any
changes in crank or port timing on this version of
the JPX.21. I read somewhere that Jammin Jay said
that the new carb was throated down smaller to
get better run times. That statement is from the
horses mouth. But that horse has also been known
to talk out of both ends.

Wow that is a bold statment :eek: the ninja is one of if not the best engines I have ever run and I have run my share of engines if this is the case I will buy two can't wait to get this engine in my truggy should have it by thursday or friday. thanks for the info

Here is a video of my modified JPX .21 in a Turmoil Buggy on our bashing track..... This engine is fantastic, it tunes easy, gets great mileage and makes a ton of power...2 seasons old and still running strong !

http://www.youtube.com/watch?v=i5qi_ImnmgI

I am offering this exact engine for $310.00 modified and broken-in......

WOW! That's a great price for one of Maximo's
modded JPX.21's. I own a JPX.21 that Maximo
modded for me. It is one bad arsed engine and
gets great run times. It has the low-end power of a .28
and the top-end r.p.m.'s of a hi-dollar on-road .21.

Sorry if this has been asked, but what is the difference between the regular JPX .21 and the Plus? I know the Plus has the cross drilled cooling head, but are there any other differences?

Hey guys, how far out is your high speed needle? Is it approximately flush, in or out past flush? Mine is out past flush and I still have a lean bog. My buddies is flush, but he doesn't have the "Plus" model. Not sure if there was a carburetor/needle change with the "Plus" or my tune is completely out of whack.

So where is your HSN needle?

the HSN housing is different on the plus engine so i dont think you can compare them.

t

you should be around flush, maybe your low speed is too lean. You didn't say where your bogging at, is it when you first accelerate or when you get up to speed?

I am bogging at high speed. I played around with the needles some more and it seems to help, but I can't be sure until I run it hard on a track. Idle is good, temp is good and ran it up and down my street for a solid 10 minutes with no bog and temping 220 with the body.

Got my fingers crossed.

Just curious, have you checked your fuel tank and lines for any pinhole leaks? That could easily cause the symptoms you describe.

Also, check the o-rings on both the HSN and LSN. The LSN o-rings on my second JPX .21 were torn from the factory.

-Howard

Fuel lines are okay. I haven't really pressure checked the tank yet, but will this weekend. I took a look at the oring under field conditions, "at the track during the night". I will take another look to make sure there are no rips. Thanks for pointing that out.

Ive seen problems with the fuel pikup in the fuel tank before.Make sure your carb is sealed real well .Any sort of air leak and it will never tune right.Your needles will be out from flush on this new carb.Make sure your glow plug is good and that it is tight.I had one of these that would not tune at all and it was an air leak at the carb base.:eek:

on my reg jpx 21 i had full throttle probs a few weeks ago and sealed the carb. ran it today and still had the same issue. put a brand new losi carb on it and it runs perfect. just wanted to drop a line and leave result conclusion. at 3 gallons its better than new and personally feel its as good as any 21 around. just pleased its back to normal

full throttle issues are usually a a piece of O-ring floating around inside the spray bar.... carb works fine part throttle but goes lean at WOT.....take the high speed stack off the carb, take the slide out of the carb and backflush the spraybar with compressed air or some nitro spray....

Breaking in the new .21 today, any tips.

I see it says improved bearing, are they ceramic or standard.

Man i have tried every break in method out there i think.And some are better than others.Just do the heat cycle method you will be fine.But make sure to use a heat gun and dont push it till you have a gallon of fuel through it.Take your time.Even after a gallon you might want to warm it with heat gun before starting.Never run it to lean and at the end of your day run the fuel out of it and use a good aro.Any raw fuel left in engine is not good and will corrode the internals.

Alrighty update time,

I got the new Plus motor in about 3 weeks ago, I broke it in using Torco 30%. I first completely sealed the engine with Lucky 7, replaced the carb insert with a 7mm and ran 2 tanks at idle, then began to tune. I ran into some tuning problems by the 5th tank and found the head bolts had backed out, I put a little thread lock and retightened them.

I did find the needle settings with the new card were slightly different from my notes with the last motor on it's 10th tank, but atmospherical changes are most likely the reason. I did change out the glow plug at this point to an O'Donnell's 99T, which worked better than expected on the old version 3 plugs to 7 gallons.

I went out the the Farm 2 and spent a day testing and tuning, basically finishing off the first gallon. I was immediately pleased with this motor, and the redesigns, I noticed the bottom end was softer and more balanced towards the top end. The buggy was freshly rebuilt, but I believe the motor balance, led to almost a 3 second drop in lap times. It was much more controlable on the bottom end, and had more top end I feel than the previous model. I do have signifigantly more runtime than my lastime there though

Currently I have about 1 1/2 gallons and am very pleased.

Outside forcast: 76 degrees, 34% humidity, Bar 29.96
Avg. running temp: 212 degrees
Farm 2 runtime: 9 m 35s per tank
Glow Plug: Odonnell 99t
Fuel: Torco 30% 8% syn, 2% cas
Carb: stock w/ 7mm insert
Sealent: Lucky 7
Buggy: HB D8 4/5/1 with Hara's world set up.
Tires: M3 Calibers

the JPX Plus to the Regular JPX to the Picco Evo2 to the Evo 3


THERE ALL THE SAME.....>Identical timing #'s THE only thing that's different is the case the head and the colors.

how are you orr whoever measurung the timing?

Odonnell temp gun/stop watch, and a regular stop watch.

That runtime is decieving a little, even with the last version I got runtimes in the 8 1/2 to 9 minute range at that track. Other tracks in the area the time comes back down to 8 minute range. I will be going to another track this weekend and will see if I get the same time comparison, I believe it will be.

the needles on the carbs have been changed...they have a new taper design on the needles which will change the feel of the engine.... As well the new needle tapers could definitely alter the fuel mileage of the engine as well....

what pipe do you run on it ? same pipe now as before ?

Both were used with an 086 pipe, but the last motor pipe had about 9 gallons on it, it was a used pipe when I got it. The new motor got a brand new 086 pipe.

some of the more "respected" members here recommended the 053 pipe with ] header for the jpx .21, does this still work for the jpx plus?

I haven't tried the .053, but I can't tell you the engine screams with a .086 with really good run times. I haven't checked to see how long the engine will run, but I am coming in with almost half a tank after a 5 min qualifier, temping 240 using the standard restrictor.

I will have to try the .053 to see if it is better, but I am happy with the .086.

086 works better then 053 IMO...

if you get a chance to run the 053 please report back about your findings!

Why wouldn't it? If you took the time to read this
thread from the begining, you may find the answer
that you want to here. Me myself, I run the 086.
The 053 killed the top end. I think the best thing
you could do is try them both yourself. Most of us
own many different pipes and try different combos
until we find the one we like. The way you drive, tune,
track size and condition, all will determine which pipe
is best suited for you.

sorry i didnt mean run time i ment how did integra measure the engine timing #'s

I have my sources. ;)

:nod: