=maz=
Member
Thanks for the reply @cjwell.
With the thinner base gasket supplied with your kit, do I need to use any sort of "goo" or just mount the base gasket and torque it up?
Blown gaskets. Is there anything that can be done to prevent it?
With the thinner base gasket supplied with your kit, do I need to use any sort of "goo" or just mount the base gasket and torque it up?
Nice Article. At the end he recommends changing the coolant for something more efficient so the bike runs cooler, but later, as a side note, he suggests installing a radiator guard.
I've always heard that a rad guard would reduce air flow making the bike runs a bit hotter. I wonder if in the case of the RC it wouldn't be better to stay off the rad guard.
Maybe he got a bit biased by his sponsors?
Another thing I noticed is that I think he got away with just skimming the head, not damage to the cylinder or piston. So maybe the damage to the engine only comes when the gasket has a small leak and let the oil gets contaminated with coolant. But if the gasket blows abruptly and the engine loses compression right away, maybe the engine doesn't suffer.
Check this out:
https://www.youtube.com/watch?v=fD_n0yIzjyI
The guy had a bad gasket and the bike seizes. At the end of the video he shows the damage to engne.
rick
New Member
I found it ...but it is a California law
California Civil Code 1793.1(a)(2):
The warranty period will be extended for the number of whole days that the product has been out of the buyer's hands for warranty repairs.
Warranty
My dealer said and I quote " We dont care if you race it and it blows up. KTM advertises it as ready to race and since that is what they are promoting we will repair the bike no matter what the use is until the warranty expires."
Seems to be the proper attitude about it I think. Ford builds a mustang gtr built for the track. They warranty it if you break it out on the track. Its built for such purpose. I feel if you advertise " ready to race" back your warranty and your machine
My dealer said and I quote " We dont care if you race it and it blows up. KTM advertises it as ready to race and since that is what they are promoting we will repair the bike no matter what the use is until the warranty expires."
Seems to be the proper attitude about it I think. Ford builds a mustang gtr built for the track. They warranty it if you break it out on the track. Its built for such purpose. I feel if you advertise " ready to race" back your warranty and your machine
reenmachine
Member
That's what I'm banking on with mine.
=maz=
Member
I have recently been in contact with KTM Australia regarding my lack of satisfaction with their products blowing head gaskets and the lack of support offered for racers.
KTM Australia have advised me that they have advised their dealers that any warranty claims with the 390's should be investigated on a case by case basis and racing the bike does NOT automatically void the warranty.
Low KM's, minimal modification...these things will be taken into account during their investigation.
There is hope.
good luck sir!! I hope the results are positive. I"ve been entertaining the idea of when the rc engine breathes its last breath and is no longer repairable to find a ktm sx450 and see if the engine would be able to fit in chassis...obviously just to use it for race purpose only. I remember when the tz guys no longer had enough spares to rebuild the 125's we were throwing in yz80 two strokes and taking them to the mini tracks. But im sure with all the electronics these days a swap of that nature may be a bit much price wise, needing the ecu and harness from the donor bike. I am sure that its possible to do. Anyways hope that you get your machine up and running as soon as possible reenmachine.
andysodandy
Member
wow we are about to buy our second RC390 and use the second as my track bike.
Is it the extended periods at top revs causing these to blow up or something else?
This forum is beginning to scare the hell out of us with all the horror stories.
I'm praying if we get the spal fan, ice and new cap we will be spared this EVER LOOMING threat while riding this bike...
Is it the extended periods at top revs causing these to blow up or something else?
This forum is beginning to scare the hell out of us with all the horror stories.
I'm praying if we get the spal fan, ice and new cap we will be spared this EVER LOOMING threat while riding this bike...
there are some previous threads about what causes it, but I think the consensus is there are milling imperfections in the head from the factory that are exacerbated with excessive heat. My plan is just to not worry, if it blows it blows, and it if does I'll just go with the thin head gasket set.
=maz=
Member
Talk to Chad before you think that this Gaskets on their own are a solution to the issue.
D
Deleted member 452
Guest
Thin head gasket on 92 octane caused detonation and the nikasil liner delamination on my bike. I was running a 12.6 AFR and removed some timing under load using my PCV but it was too late. To be fair, there were some other issues with my motor: It looks like the timing chain wandered into the head, cylinder, and block and then recentered itself which flushed a lot of aluminum shavings through my motor over the last 9K miles. It was probably caused by my KTM dealer installing the front timing chain guide incorrectly when replacing the head gasket under warranty @ 5K miles so I had to buy a new motor AFTER THE WARRANTY EXPIRED last week. I still recommend using the standard thickness Cometic head gasket unless you weigh 100lbs and live in Kansas (flat) or use race gas all the time.
D
Deleted member 452
Guest
Found one with only 107 miles on Ebay for $1.3K. Tore it apart a couple days ago and sent the top end to Chad to check cylinder deck flatness, skim the head, and some other goodies. I hated to take a apart an almost new engine but I want to avoid the head gasket blowing at 4.3K miles again.
I think i may have a water pump issue i drained the coolant and then flushed it with a hose ready for water weter .changed the oil then rode it about 200 yards in first 5000 rpm ish just to warm it up to look at the level hot . The sight glass was full and white looking i now have water in the oil. the old oil had no signs of coolant so it had to be me what was your water pump issue i tried to find it in a search but cant find any details thanks in advance
D
Deleted member 452
Guest
My bike didn't overheat when the water pump died but a lot of coolant was in the oil (didn't see any oil in my coolant). It took 3 oil & filter changes after the water pump was replaced to get all the coolant out. The sight glass showed a little condensation 'till after the final oil change and a long ride.
=maz=
Member
Water pump seal went on one of ours...then the head went.
When the head gasket has gone I've never seen any oil contamination because the pressure difference forces the coolant into the overflow bottle rather than into the motor.
When the head gasket has gone I've never seen any oil contamination because the pressure difference forces the coolant into the overflow bottle rather than into the motor.
thanks for the responds both of you i made it out to watch the race and asked about some of the 390 racers thoughts there dose seem to be a reoccurring head issue if you race them as every one points to that as soon as i said i had water in the oil but it cant believe it is in this case but i will start with the pump as it looks like the cheeper option
Mkinzer126
New Member
Reviving this thread... Has anyone had any head issues with 2016 models or the revised KTM cylinder/piston part numbers?
No issues on a race bike (2016)
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