Jansen destroys Rotax in record time?

[Brad Linkus]

Was that your head I was looking at Mike?

[Anonymous]

Well…… Good God, I hope you got 20 laps first!

[Mike Jansen]

yup that was my head that you diagnosed.
the stud into the cylinder at the base was loose and so was one of the bolts on the other stud. I’ve got to call Acceleration Karting about this. Rebuild on the engine and they didn’t replace the connecting rod bearing (it failed so I know my breakin procedure was followed correctly)

Brad, thanks for the diagnosis. When it comes to engines i won’t doubt what you say!

Better to have happen in testing versus on race day…

[Mike Jansen]

Rick,

33:1 fuel oil ratio
160 main jet
2 heat cycles at 7500 (both 15 minutes)
2 heat cycles at 9500 (one @ 10 minutes, one @ 15)
today: 1 heat cycle for 15 minutes @ 9500; 1 cycle @ 10500 for 15 minutes…
Final Break in period: 2 laps @ 11500 then the engine quit when the piston hit the spark plug and the ceramic insulator broke off… Cylinder good, piston and head bad…. I cut the seal since I KNEW I broke it in correctly…

Doubt it’s going to be fixed and back before club race this weekend @ IMI… And the engine was running strong….

:bang

[Anonymous]

Holy cow, sorry Mike. 😥

what kind of break in oil were you using?

[Rodney Ebersole]

Rich I don’t know of any oil that will torque bolts properly.

[Doug Welch]

Starting the 20 lap excuses a little early aren’t we Mike?

[Mike Jansen]

There he goes, kickin a guy in the pills when he’s down!!! 8)

Like I said Doug, better in testing/practice versus race day! 😀

[Anonymous]

I can’t believe acceleration didn’t torque bolts!!!!!!!!

I was wondering what oil did you use in the gas for break-in?

[Mike Jansen]

nice smelly beans, err bean oil…

[Anonymous]

So what did Acceleration say?

[stacey cook]

Hey isn’t Grand Junction Motor Speedway just over the Hill? and aren’t they a Rotax Service Center 😥

[Mike Jansen]

Stacey,

I went back to my home town of Vegas for Christmas and brought the engine with me since I drove (rented a car and made it from Longmont under 10.5 hours but that’s another story)

Anyhoo, I wasn’t thinking…
FYI… Acceleration wasn’t happy about it either and they are fixing it under acceptable terms.

Stacey, next time since I’ll have it done after season’s end…

To all you fellow rotaxians… I’d suggest you get a top and bottom end done if you’re putting 30 hours on your engine or are racing and you weigh in around 200# Better to have an expense up front versus having to pay again when the bottom end goes. Brad, Stacey, feedback please…

[stacey cook]

Mike, Just giving you a hard time 😀 Curtis and the guys at Acceleration do a great job… I agree on the 30 hours when you take your weight into considerartion but overall they have been really durable..

[cgordon]

Hi Mike,

I think that a rebuild every 30 hours is a bit of overkill. It’s possible to save some money by sticking closer to the Rotax recommended rebuild intervals without risking major damage. The Rotax manual suggests 50 hours between rebuilds. I asked Andy Seeseman (who’s a 200+ pounder) about this and he suggests a top-end at 20-25 hours and a complete rebuild at 45 hours.

Charles

[Author]

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