Jammin JPX 21 Plus ( new)
 

I had to wait a while to get a new Jammin 21 from my local crackhouse, and when it came in it was the new Plus version. I see the head has been drilled,and carb is a little different. I plan on breaking in starting later today.Does anyone know if theirs any other changes to this engine. I cant wait to try this .21 in my truggy. I have been running .28 Jammins for acouple years with great luck.And I will be watching my lap times to see if they improve. :D ;)

Not that i'm aware of. I'm waiting for Maximo to get
his hands on one. He will measure the crank and port
timing up and let us know of any changes. Please let
us know what you think of the new style carb.

I just picked mine up yesterday from the LHS. I havent had a chance to start the breakin process yet but I must say it sure is nice and shiny outside :)

jpx .21
 

Any pics of the new engine

+1....lets see some pics!!!

it looks the same minus the holes in the cooling head and all black carb with plus written underneath/below the jpx.21

Ended up waiting to go get a new flywheel instead of one I had. Looked a little closer and saw a little wear on the pins. So I didnt get to fire my new .21 plus today. No hurry been raining for days, are big club race of the year,rained out both days. I will get back with some info when I can. Theirs more info on this engine in the Ofna site, they just put it up a day ago. And their are internal changes. Look under Press Release in the Ofna site. ;)

Here is the press release....

Just started bench break in tonight. After preheat, this engine fired with just one bump and sat their and idled perfect. Ran a couple of tanks and a few heat cycles tonight, and will pick where I left off tommorrow. Myself and a couple buddies where very impressed with this engine so far .:D

hmm if jammin got the runtime up to 9-12 min i will be impressed. old jammins were getting 7:30-8:00 of fuel

picco is Notorious for changing timing #'s without informing any one of the changes.....so it wouldn't surprise me too much to find out they once again went and tweeked the #'s....but there again i would never run one stock as max would already have his sticky finger's on it before it ever saw fuel. :lol:

If runtimes are increased I may now have my new favorite engine!! I always loved the Jammin mills but 8 minute runtimes dont cut it here

I hear ya buddy....in stock trim they really suck in the fuel dept.

Integra, I never ran a stock Jammin .21 before. I know their fuel mileage sucks ! I will run this engine the rest of the year, Only about five races left around my area. I will see if the timing changes help on mileage.And I will have to try my next Jammin .21 done up by Maximo.

you wont be disappointed with a clocked JPX....I can guarantee that. :nod:

I got the chance to break my motor in over the weekend. I have the JPX Plus.
I tried several different pipes on it and the one that seemed to work best for me was a Werks 053 pipe with a double bent header from SH.

With this combination I was running the motor right around 190-210 degrees throughout the day. With roughly 3/4 of a gallon on the motor I hitting 10 minute run times with no problem. The longest run I got out of the motor was just a hair over 14 minutes.

I must say so very I am extremely impressed with this motor. The only thing I want to know now is how many gallons I can get out of it!

I dont now that it matters but I did take the carb apart and seal the needles and carb pinch bolt. I checked the front and rear of the block but saw no leaks so I didnt do anything to seal the block itself.

http://i246.photobucket.com/albums/g...roZr/bz004.jpg
http://i246.photobucket.com/albums/g...roZr/bz006.jpg

hmm looks good. thanks for sharing your review:nod:

i would be impressed if the run time's kept up with that....but knowing these motor's the run time will come down as the motor break's in...you wont feel full potential till over a gallon.

NeoNot, thanks for the review. At 3/4 of a gallon, how is the pinch on the engine?

Please keep us informed.

Picco's hold mechanical pinch for OVER 2 gallon's....Dont be surprised to feel it even longer then that.

Picco's have THE HARDEST cranks in the industry...ask any modder and they will tell you the Picco cranks Eat Bits/file's alive they are so hard.....the Only thing i would HIGHLY stress is a New rod after break in....with the crazy mechanical pinch the rod tends to take a beating during break in and the initial running of the motor....Get a rod to be safe.

at 9 to 10 minuets on fuel. is still agood deal for $220:nod:
enignes are getting really competitavie for the 250 and below price tag.
odonnell super sport .21
jammin plus .21
reedy .21
orion .21 alpha standerd
novarossi pl5xl .21
too many too choose from lol:nod::sweat:

re
 

I dont know why you guys are not getting longer run times I have an old jammin in my crt x2 it has about 6 gallons on it with a werks2013 pipe i ran from start to stop and had eleven minutes run time same with a picco evo2r same pipe same truggy and had closer to twelve minutes run time

Runtimes on these jammin's are affected in a huge part by setup..... I get fantastic runtimes with these engines with all the power anyone would ever ask for...IMO these are very underrated engines

What pipe would you suggest? I have heard the 086 pipe works well with this engine.

I run 086...also like the JP4.....many people have also said the 2013 really gives wicked runtime !

It is every bit as tight as it was before I started breaking the motor in.

As fas as the con rod goes. I have seen no ill effects to it at this time. I have been using a heat gun to get the motor up to 200 *F before firing the motor so this may help a little as well.

I still think I might be able to squeeze just a little more run time out of it. I am still a little rich on both the low and high side. It isnt a lot but there is still some room for adjustment.

I am not sure what everyone else likes in pipes but I tried several out last weekend looking for changes in power, heat and run time. I tuned the motor each time I ran with a new pipe and none of the pipes gave me better run times than the Werks 053.

I also tested an OFNA 063, JP2, JP3, SH 2060 and an RB Concepts (dont know what number it is).

The 053 seemed to offer the best overall preformance. I had good bottom end with a respectable top end.

I dont know how much of a difference it mades but I also tried four different headers as well. Double bent header from OFNA, double Bent header from SH, short curved and long curved header.

In the end I went with the SH double bent header. It seemed to offer a little more low end punch with a minimal increase in run time for me.

I was getting 11 to 12 on mine, but that was when I some how changed my radio settings and tuned the motor with the barrell only opening to 3/4, but still had a tonne of power and ran 220-230

I noticed the barrell, adjusted it and was way to lean up top 280-290, and had rediculous power, to much really. After bringing run temps and putting the proper tune on it, the run times dropped to 8- 8 1/2.

I am not concerned about overpowering the track and would like to increase runtime and decrease power. A few recommended the 7 mm Picco inserts, has anybody tried these or found something different.

just tune the radio to not give you full open throttle.....

wow im getting like 6 min runtimes out of my jammin with a 053 pipe. i could still lean it a bit on the lsn. but are you guys that are getting 10 min runtimes running on a small track? like not on the throttle too much? because my local track is on the throttle always pretty much. like almost wide open. so whats your track like? i would like to know

Are there any fast guys going 10 at your track? I don't care about slow people, what are the fast guys doing?

If none of the fast guys are making 10, the track wont take ten and you're not at much of a disadvantage only going 6. If fast guys are going 10, you need to rethink your set-up.



As for the 2013, great mileage pipe with good power. Runs a bit hotter than some others though.

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:lol: oops

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.

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 !

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

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.:D

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!

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.

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....

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

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...