RACERS! Reliability Report.

[Superpacman13]

Dear fellow racers, I am curious about how the reliability has been with your track RC390? If you have had issues what are they? To start this off I have had a blown head gasket, valve retainers fail and take out the exhaust cam, and a piston crack in half. I am looking to see if there are issues that are consistent such as the head gasket.

 

[Andy]

Here's an interesting thought, chatting to one of my local dealers who runs a youngster in the KTM Cup, he said the bikes are really good with the odd gasket failure. However Ind the Cup they run all bikes with the throttle restrictor, wonder if that makes a difference? Of course most (other) racers would run their bikes unrestricted.

 

[isaac_]

No issues that were not created by myself (i.e. Disconnected AIC) but otherwise as healthy as a horse.


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[big_sur]

We've had 5 RC390's race in our club. All five, including mine, have blown head gaskets.

 

[KTManny]

No issues that were not created by myself (i.e. Disconnected AIC) but otherwise as healthy as a horse.

How many miles Isaac?

 

[isaac_]

No issues that were not created by myself (i.e. Disconnected AIC) but otherwise as healthy as a horse.

How many miles Isaac?

When I bought it used it had under 2000 miles. I've probably put in 1000 track miles since then.

Edit: I'll add, I've highsided the bike 2x... and she still runs strong.

 

[=maz=]

We've had 5 RC390's race in our club. All five, including mine, have blown head gaskets.

3 out of the 5 that raced at my track blew head gaskets also...2 bikes did it more than twice.

 

[Superpacman13]

We had a race this weekend. Add two more headgaskets to the pile

 

[CDN Duke]

Have the bikes with head gasket failures had higher RPM limits by any chance? Not sure if that's a factor at all? I have Akra map with raised redline (10250 iirc). I wouldn't want to raise it any further that's for sure, no power up there in any case.

 

[mdabyo]

My question would be, of those who blew head gaskets did they blow more than just the head gasket? that has always been my worry, i dont mine blowing a gasket, worried about additional damage when it goes.

My 2015 has been raced for 2 years now and still going strong. some other issues, i cant get them damn thing to idle worth a damn, but runs strong in races.

 

[Superpacman13]

We race at Portland International Raceway, its an incredibly fast long course. Our bikes run the standard 10250 RPM limit but PIR is two drag strips connected by a few corners. Very hard on these little bikes.

 

[big_sur]

I know at least 3 of our 5 have not had raised RPM limits, not sure about the other two. They have all blown up at different rates though, some last longer than others.

 

[snaggletooth77x]

I've blown mine a few times so far!

 

[CDN Duke]

I've blown mine a few times so far!

Ah, interesting. Was anything resurfaced in between? Assumption being that it's manufacturing or assembly defect. If latter, just replacement should be fine but if the head / deck need to be resurfaced, that to me would be a required step in the rebuild?

 

[Superpacman13]

Ah, interesting. Was anything resurfaced in between? Assumption being that it's manufacturing or assembly defect. If latter, just replacement should be fine but if the head / deck need to be resurfaced, that to me would be a required step in the rebuild?

He is being a smartass, I am his engine builder. Yes everything was swapped surfaced etc.

 

[snaggletooth77x]

Ah, interesting. Was anything resurfaced in between? Assumption being that it's manufacturing or assembly defect. If latter, just replacement should be fine but if the head / deck need to be resurfaced, that to me would be a required step in the rebuild?

Yes the head was resurfaced and has been every time the gasket was replaced. Assembly was by a reputable source who I race for and has been working with these bikes from day one. This has been a know manufacturing issue and we are working on ways to stop it from happening.

 

[cjwell]

Every time you surface the head it becomes weaker and more prone to failure. If I have to take more then .004 or 5" total off it from new it gets replaced! By machining it you're just removing material in the exhaust bridge making it thinner each time where the warp.... Quit machining it and replace it.

 

[KTManny]

Every time you surface the head it becomes weaker and more prone to failure. If I have to take more then .004 or 5" total off it from new it gets replaced! By machining it you're just removing material in the exhaust bridge making it thinner each time where the warp.... Quit machining it and replace it.

Is there any kit or mod that can help prevent a blown head gasket?

 

[JBinSD]

Wow, interesting thread, I'm considering an RC vs. R3 for racing, should I be properly scared? A race ready R3 in So Cal is about $3k more than a KTM. . . these failures seem to be the reason. . .

 

[JBinSD]

wow, this thread petered out quickly, at my local track, people seem to be running from their fully-built RC's to R3s. Makes me wonder if its an opportunity or a warning. . .