Three bottom ends

TKF Racing
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Rockaway, NJ US
TKF Racing
Edited Date/Time 8/26/2013 5:42pm
Need some serious help

Here is my time line
2010 - buy left over 2009 KTM 125 SX - still new right off of the floor - son breaks arm and mainly rides his 85
2011 - my son rides the 125 but not real hard yet - we replace the top end once in the middle of the year...fun year watching him improve
2012 - he starts to ride pretty hard and we practice every weekend and race almost every other....replace top end twice during the year...scheduled these so no time was missed and he is getting pretty fast
2013...4th weekend just before first race, we have the top and bottom end done - hot rods bottom end vertex top end...three weeks later bottom end blows up...shop said it was bad connecting rod and just bad luck....have top and bottom end done again...hot rods again and vertex again along with cylinder plating (at suggestion of shop)...they also suggest to run the mix a little richer...go to 32:1

Today, first time out after having all this done with richer mix...same thing....bottom end again

Any ideas from any one?????

Thanks for any help
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TKF Racing
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Rockaway, NJ US
TKF Racing 8/4/2013 6:38pm
8/4/2013 6:38pm
every one I have talked to says the hot rods and vertex were just as good a the KTM parts,,and the KTM parts are expensive as all heck...looking back, for what we've spent so far, I could have gotten OEM, but i didn't think I would be buying two of everything plus a replate
captmoto
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Rancho Cucamonga, CA US
captmoto 8/4/2013 10:59pm
8/4/2013 10:59pm
What exactly is breaking?

The Shop

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Jakes Dad
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Brooksville, FL US
Jakes Dad 8/5/2013 4:53am
8/5/2013 4:53am
I'd like to see a picture I'm guessing crank not being centered or something related. I've never had a premature failure with a hot rods other than inhaling sand one time on a supermini. Racing up to 3 different bikes in a season I've probably been through 12 hot rods cranks in last 7 years. I mainly have them rebuilt by TDC 2 Stroke Performance now.
rallendude
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Adger, AL US
rallendude 8/5/2013 8:50am
8/5/2013 8:50am
OEM cranks x2. I prefer OEM parts on a stock bike that is going to be ridden hard anyway. Check your jetting. I highly doubt it's "bad luck" or faulty con rod. The bearings are what goes. Lean jetting will cook a bottom rod bearing in no time. No coolant will also. How's your water pump seals?
BAMX
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BAMX 8/5/2013 3:37pm
8/5/2013 3:37pm
I have Hot Rods and ProX in my 125...30 plus hours with no issues.
pete24
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Marlborough, MA US
pete24 8/5/2013 5:51pm
8/5/2013 5:51pm
the ktm crank is expensive for a reason you get what you pay for what i dont understand is all you ktm lovers claim your bikes come with the best stuff stock, then you put rubbish chineese parts in them when you "fix" them
slipdog
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slipdog 8/5/2013 6:31pm
8/5/2013 6:31pm
^^^ This addition of Real Talk was brought to you by pete24, next week we'll have scooter5002 here to discuss the in's and out's of choosing a 500af conversion company.
scooter5002
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scooter5002 8/5/2013 7:20pm
8/5/2013 7:20pm
LMFAO. I can start the 1 800 FUCK MPS hotline up early, if anyone needs the help.
mynewcr250
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mynewcr250 8/5/2013 9:44pm
8/5/2013 9:44pm
im with the other poster...what kind of failure are we talking about?
madmaxperformance 8/7/2013 9:33am
8/7/2013 9:33am
The other thing you should do, is make sure you are running good gas. Maybe mix a bit of race fuel in, even at 25%. Detonation will pound big end bearings out in no time. Cheap cheap insurance, that and make sure your jetting isnt too lean, causing detonation.
Jakes Dad
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Jakes Dad 8/7/2013 10:00am
8/7/2013 10:00am
Again "installation problem"...............
Sheriff245 8/7/2013 5:15pm
8/7/2013 5:15pm
I am with Jakes Dad on this. I have installed a few Hot Rod cranks, including a stroked one that has now over 40 hours on it and I've never had a failure. One bad part is a possibility. 3 in a row isn't. There must be something more to it.
TKF Racing
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TKF Racing 8/25/2013 6:11pm
8/25/2013 6:11pm Edited Date/Time 8/25/2013 6:12pm
problem solved....there was a crack in the case...the first shop we took it too never said anything to me and used jb weld to put it back together

the motor is now completely rebuilt with a new case, top end, bottom end and clutch
Jakes Dad
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Jakes Dad 8/26/2013 5:42pm
8/26/2013 5:42pm
Aah Haa! Yeah that'd do it.

Back when the new style KTM 65 came out they had a cracking case issue back by the countershaft. Saw a couple guys smoke the bearing due to the load flexing the shaft after the case was pushing apart. Must have been something similar with the flexing going on.

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