Let's rehash micros

[Mark Parker]

so now that they have been out lets talk about facts and not speculation.

how do the new factory evos stack up against the prevos with the kit?

i know that a new out of the box evo walked away from the field at Ocala a week or 2 ago but the driver is pretty legit.

I know I’ve heard they run best around a 100 jet.

Has anyone put the new piston and con rod in along with the proper squish vs just bolting on the kit? How’d that manage?

Id really like to run rotax this year and would prefer to not waste thousands of additional dollars chasing a halfway decent setup.

 

 

 

[Christian Fox]

Not nearly enough data out there yet as so few have received their micro upgrade kit. You can’t possibly draw any conclusions yet. Couple that with the fact that micro drivers are all over the place in terms of ability and it’s further complicated. I will know soon enough. I know what my kid/motor combo is capable of at our home track, so a back-to-back will be pretty straightforward. In another thread, Mark from Arizona said a couple of drivers had brand new Evos, but both were faster when they swapped the upgrade parts over to their prevos. Hardly a conclusion, but I truly believe a really good, part selected prevo will smoke a stock evo (unless you win the lotto with your stock motor).

[Steve piggott]

testing today for the first time with the upgrade, on test run up and down our street. driver said it pull harder than before. 110 jet

[Steve piggott]

i know less now after our first test day than i did before we started. Tried every combo possible and didn’t find anything that worked, from a 104 up to a 118, never got rev above 8810, tried half throttle to full, tried needle pos from top to bottom,,,,,,,,,,,,,,,,,, totally lost,,,,,,,,,,,,,,,,

[Mark Traylor]

We still have not received a micro upgrade.   The people that have upgraded engines here (from parts off of brand new engines) have had no plroblems tuning.   Just the opposite in fact.  My first reaction has been that people are running them far too rich and I think many have been but I now have heard of two people that have run them lean and rich with still having lots of problems.

 

 

[Aaron LaRoque]

Ok, we just returned from Can-Am round 1 in Tri-Cities Washington and I was running my old motor with a newer lettered cylinder I was able to buy used off this website forum, as I had a 2010 cylinder on Diego’s old motor, with the EVO upgrade kit parts, stock pipe from Rotax.   The big news is, Rotax now has a new throttle slide limiter just like the old brass one for the cap, only its a little shorter than the old one so you cannot use the old one.  The new slide limiters are going to be mandatory so I expect Rotax will be sending them out soon or have them available soon.  I was running a 110 all weekend pin 2, I heard some were running as low as a 105, so somewhere in that range.

[Aaron LaRoque]

Also, I know some will ask, why am I just not running the stock new EVO i bought?  The answer is, I have not had time to test it, the motor is still sitting in the box,  I will eventually get around to doing back to back testing with my evo upgraded motor vs. my new evo motor.

[Mark Traylor]

Thanks aaron.   Sounds like a brass slide stop will wear out pretty quickily.  the old steel ones would wear out.  Unless the brass is thick enough to reduce the contact stress significantly I would be expecting to check those regularly and swap them out more often.

[Anonymous]

Has there been any word from Maxspeed on the availability of the Micro kits?  It’s a tough situation down here as some in the class have either the EVO motor or the upgrade and are now much quicker than the non-upgraded motors.

[Mark Traylor]

It is a difficult issue on both sides.  Were are racing split and the points are being adjusted but that doesnt change the frustration of a 9 year old kid.

There have been some micro kits shipped witht he wrong exhaust stinger.  Maxspeed has a list and they are working it but I know at least 2 guys in SC that got the wrong one.  If you got a kit with no turndown on the stinger they sent you the wrong one.   Give them a call so they can get it taken care of.

In CanAm they had to turn to outlet to point up instead of down because bumpers were being melted by the exhaust.

[Mark Parker]

If our 2nd closest to home track wasn’t kershaw I’d sell all this rotax shit. What a bunch of garbage

[Steve piggott]

found some success this weekend, 112 jet,, floats on the leaner side, pin #3 slot, one key was limiting the throttle . To much and the engine 4 stroked. we are not the fastest but are close. We do not  have one of those super motors just one off the self . seems like top motors are reving higher? only getting 9333 or so.

[Vincent Ciolino]

We received our kit and I have found a silver carburetor sleeve so I assume we are supposed to be using one now?  Anybody else get one with there kits?  I sent an e-mail to Maxspeed asking this same question.

 

[Vincent Ciolino]

Just got word a bulletin will be released to address the additional part

[Mark Parker]

They shipped me something today but not sure what it is.

[Jerry Brown]

We have seen good success with an out of the box EVO – like has been mentioned – the driver is exceptional. Continue to do what you know how to do and you will find the power. We are a long way from having this figured out but are making progress each and every session on track. Correct me if I am wrong – I understand the following things thus far 1. No throttle limiter is required. In fact if there was one I would find it to be an additional problem given the new motors struggle to attain anywhere near the top RPM’s the older packages were capable of.  It is also my understanding that the ONLY allowed Jets are those in the package delivered with the engine – that is range 115-130. The engine comes with a 130 installed, after break in you know what to do with that. Ours got tore down at the first race – We had to reseal and looking at the pipe now after some slight tuning changes, she is still running on the lean side – we have a lot of work to do jetting and clip wise and dealing with the same old micro issue  – too big of a carb for a little zinger like this. Just noticed the new twin air filter comes pre soaked with oil – looking forward to running it dry (not done yet) and getting some clean air in there. This is going to be a real challenge working toward Kershaw in 2 short months. We have had no issue what so ever with the wiring or the quality of components YET.

 

[Christian Fox]

Jerry,  an evo micro can’t be run with any success without limiting the throttle. You will have massive low end bog and limited top end. People were having so much difficulty finding the right slide setting, Maxspeed is now shipping a throttle stop similar (slightly shorter) to the old fr125 piece. It is going to be a mandatory piece (this is a good thing). With the throttle stop in place, we average 200 more rpm on the top end vs. our old fr125 setup. Without the stop, we were 200 rpm lower. The exhaust header is 4mm smaller in evo form; you can’t expect to just dump more air than before with a smaller exhaust outlet and get good results. And, no, jetting is now open for evo micro; most guys are way leaner than a 115. Set up correctly, an evo (new or upgrade) is way faster than a fr125 micro. Not even close, actually.

[Mark Parker]

Jerry has an full from rotax evo and won the last Ocala race by a lot with it. I’m not writing what he says off even though it’s different than what we’ve heard about the evo upgrade motors.

[Christian Fox]

Mark, it’s not a matter of writing anything off: the carb stop is mandatory now. Whether or not someone thinks it helps is moot, you’ve got to use it. The reason Rotax has mandated its use is people who figured out where to limit the slide were much faster, and the people that hadn’t figured it out were struggling/complaining. I’m just relaying what I’ve seen at the first two races at home and what my engine builder saw at the first CanAm race.

[Aaron LaRoque]

Before the slide limiter was mandatory, I was running a 115 to a 118 in Phoenix and was getting good power, more than I can get with the limiter installed, I was limiting the throttle a certain amount but no where near as much as the slide limiter is limiting it now.  With the slide limiter we are getting much less air in the motor thus the reason for dropping down to a 105 to 110 jet range.

[Jerry Brown]

Ditto LaRoque – Same here, the limiter (thanks whoever came up with this) – Put us right back at Square 1 – day 1. We were making progress  – thank god for the new jet range as the old WILL NOT work with the limiter. We are getting ahead slowly but surely – this is tough…….

 

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