[Eric Jacky]

just got this from my Rotax contact. They are aware of the issue, and they believe it is not electronic, but rather not enough RPMs on the low end, and the engine is just choking off.

“We have come up with a solution to this problem, but many times the problem was one of the engine not rising up in RPM’s. We had a special sleeve made for the carburetor. It is CNC’d, and is 33mm long to put inside the cap of the carburetor.”

They shipped a bunch to Maxspeed, but I’m guessing its not going to be cut and dried getting one.  I’ve reached out to our dealer (who learned about it from we, the customers) as MS has apparently not sent out info.  She is going to try and get me one, but not making promises.

this jives with what I’m seeing the last couple days with others in our class getting their kits with a mysterious new piece for the carb that wasn’t there in our kit.  So hoping that helps, now its a matter of getting one!

[Eric Jacky]

Luis, they definitely like to be rolled on vs stomped on.  We’ve noticed that as well.  I’m no jetting expert by any means, but I’ve traditionally heard “popping” is associated with being too lean.  We’ve been running best at 115 in high humidity for our micromax, but the junior may want a little more. 118 may simply be too lean for your conditions.  I’ve reached out to Rotax about the coil question and so far have not heard anything back.  After spending a nightmare month chasing this EVO, I’m two seconds from getting an LO206 and being done with this Rotax stuff.  Lots of frustrated folks down here in FL.  We’ve at least had ours for a month, most people are just getting their kits this week.  Plus they are saying the kit is now including a throttle slide stop which it didn’t before, which tells me they realize there are problems and are trying to do something about it.

[Eric Jacky]

Well, you just described our weekend to a tee.  Our Evo failed seven times over a double header weekend.  Practice, qualy, Premain, main events, completely random, never permanent, my little guy  fought to keep it alive.  We bought a new battery, we swapped the layout of the battery box so the kill switch is now in the back.  I didn’t give a thought to it being the harness/ecu until I just saw your post.  Def sounds like there may be a bigger issue.  We have our ground on the correct cylinder head bolt, so we don’t think that it is.

[Eric Jacky]

We tried a 122 in our micro and still have a lot of bog (came from 130).  We’ve changed the clip to 1, the plug to a 31, nothing so far eliminates it.   We have a 115  jet waiting for us tomorrow (race day), so hope to try it in first practice and see how it works.  Our times are staying relatively stable as we’ve been experimenting,  but zero increase in performance that we can detect.  It seems a little more robust at the low end, but still seems to bog down on exit.    Contrast that with someone who used a full Evo at the first race (he knew it was not legal yet), but that kid flew by us on the main straight a couple weeks back.  So looks like its going to be a rough weekend.  (the cynic in me is trying very hard not to think that Rotax just shoved out a handful of update kits that really don’t do much, knowing we’d be forced to go buy a full motor if we want to keep up)  Trying real hard.

[Eric Jacky]

Thank you Mark and Bruce, I’ll try those things you suggest.   We gotta figure out something quick or just plan to put the old system back on for the race this weekend.  Will see how it goes Wednesday evening.

[Eric Jacky]

We received our upgrade kit for our MicroMax last week and were able to run it this weekend at Orlando Kart Center against a non-upgraded micro.  Our initial impression is not overly positive.  We spent all day trying to get it to run.  We started with the 130 jet, and went down as low as 125 before settling for 128.  We tried various plugs.  It never ran right, we could put it on the stand and run the throttle flat out, never getting more than 8700 rpm.   We would normally expect to see upwards of 11,000 unloaded on the stand. On track we hit 8600 for the most part, well short of 9400 we would normally expect under full load.

Our lap times were hit and miss. We saw one 65 second lap, (by comparisons, FWT kids were hitting 60s.  My son is relatively new, but it was discouraging for all of us that it wasn’t remotely faster.  The one difference we did notice that was positive was the low end grunt, but on the two long straights at OKC, you could hear it basically rev limit half way down the straight and that was it.  We hit 50mph once all day, we normally hit 48-49, but spent all day basically where we are usually at with the normal kit.  We were expecting to be able to achieve at least 52-53 or more with the new kit.

I see people talking about 115 jets, we didn’t feel comfortable going that lean, but might try it wednesday ahead of the next Ocala Rotax race this weekend.  In the end, I have a feeling we’ll go back to the standard setup, we need RPM at Ocala.  Wish these kits would have been available to test sooner than after the season’s already started.

[Eric Jacky]

We don’t know for sure.  He stayed alive during the final on Sunday after we spent all weekend chasing it, but when I watched the video last night, I’m pretty sure it was cutting out.  After I saw your post about your issues, I sent an email to a Rotax rep who helped us with other issues and let him know.  We only have a week to next race at Ocala, so hopefully can get it sorted by then.  Hoping they can send a new one that we can try.  When it runs it runs brilliant.  Unfortunately, it is not 100%.

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