Cool, Danny and Dean r really cool guys. I'm glad 2 b of some help.

tnx for the info pooh2..

I busted my brand new pipe today, but right before I finnaly got the tune of my Ninja .12 just right( doenst have a gallon on it yet), and DAMN!!!. It scare the my pants off! I was also having problems with the steering not centering, so I coulnt really push, but on the straight the thing just lights up.

Mow I just gotta finish break in on the .21.

I picked up my CRT Pro today and dropped in the Ninja MR21B01A w/ JP-1 and I'm telling you brother this thing SCREAMS. You'll love it.

This morning I was on the ninja website and noticed this...

http://www.ninja-engine.com/content/...ng=0&serie02=1

Anyone has a grasp on how changes are those Serie 02 Rev. A to the 'non Series 02 Rev. A'?

At first look, seems that nothing changed, so the changes should be more subtle.

hello,

I'll soon change my engine, and I think take a mr21 r01a. I would like to know the level power of this engine against a xenon (not the R)? for the people who use this engine, what is the main part that you change frequently? the rear bearing? the rod?
if you have some critical (bad or good) about this engine, I take

thank for your answer

The "A" version and the "02" version are the same thing. Example: MR21 R01A = 02 version.

I have Ninja engines for almost a year and I can assure you (as many in this thread could) that power output of the MR21-01 is really great, maybe they don't have the rip of other engines, but it makes it easy to drive it hard (laptimes are there... and easy to do).

The carburation is very stable and sensitive to changes so you will not battle with it. You could do easily 5 minutes with the fuel tank so runtime isn't a big problem except in some tracks.

Comes with the 8.5mm carb venturi and gives good power and runtime. You have the 9mm too if you want 'a little more' but runtime suffers a little.

Is a great engine. Get the engine, pipe and a pair of headers (long and short) and see what suits for your local track.

I don't know in the new units, but.. you need to raise the combustion chamber. Before starting, do a look on the previous messages on this thread just to get what worked for the people and values and compare them with the ones you get from your engine.

The 'gripe' could be the price of the plugs, but... I've been using Sirio ones and work great with them (and of course, are way cheaper). Taper isn't the same, but... after a full year of using Sirio plugs I didn't had sealing problems on the plug.

Well... got one unit of those marked with a '02' on the crankcase (Series 2) and found now some subtle differences, need to do a complete teardown to see what changed between the originals to that one unit.

Seems that Ninja is making some running changes between engines without changing the model number.

What I've found so far is on the carburetor.
- Carburetor retention mechanism (the original didn't came with o-rings and the 02 comes with o-rings to improve the seal).
- Low-end needle. The original came with a blunt shape on the needle and the 02 comes with a conical shape, this changes the fuel curve vs. barrel movement. Cannot confirm, but... the spraybar seems that changed too. This could affect to the power curve of the engine.

This weekend I'll do a complete teardown of the two engines and see what changed. But... seems that are subtle changes rather than revolutionary modifications. Cannot assure it 100%, but... seems that sleeve received too some slight changes on the underside.

hey guys i was running in my mr12 engine in 2day and before i got it started it locked several times, does this cause damage to the engine?

If the engine locks is due to the massive pinch they have, some units need to be pre-heated before staring just to alleviate the massive pinch and make it easier to the conrod and other parts and materials.

You can cause some harm to the engine (conrod basically), use a hairdryer at least to heat it a little at least on the first start-ups. After, when the break-in finished it will not lock itself on the TDC.

which is the best plug for a RO1A on 25%

Hi, I recently purchased an Ninja MR12-T01 and have been trying to get it started and run in. Everytime I placed the car on the starter box the engine was so tight it would just not turn over. Even after heating it I still could not get it to turn over. So in desparation here's what I did. I heated the engine, removed the plug, sat it on the starter box, got the motor turning over with the starter box and while it was turning over I stuck the plug back in, tightened it up, put the glow starter on the plug and the engine fired up. Ok probably not what the experts would recommend, but as I said I was desparate. Anyway have run about 10 tanks through so far and now starts like a dream.

Ninja plug #7, but... I routinely use Sirio #7 too. Have different taper, but I'm using them for more than a year and never failed me.

cheers mate