Turbo snowbike questions

[4strokesnewbie]

Last year I ran a boondocker turbo on my KTM 450SXF without much success. I did not do any internal engine mods. I was running 105 race fuel and 8lbs of boost. My 2 engine failures were both from excessive heat at the piston. There was no signs of detonation in either failure. This was a boondocker rear mount turbo. Has anyone else had good luck with this setup and good reliablilty? Any tips to keep from melting down? I currentry have the head off of the bike and now would be a good time to make changes if necessary.
In the meantime, I'm riding my Husaberg. Any help would be greatly appreciated.
Thanks

 

[swedenturbo]

I cant tell you whats wrong. You're running low boost and good fuel. For me, that has worked very well. Boondocker hasnt had good reputation in their turbo kits. Plenum size, fueling and intercooling are some of the issues to look at. Maybe go for a KMS upgrade? A custom made low comp piston?

 

[4strokesnewbie]

Thanks

I cant tell you whats wrong. You're running low boost and good fuel. For me, that has worked very well. Boondocker hasnt had good reputation in their turbo kits. Plenum size, fueling and intercooling are some of the issues to look at. Maybe go for a KMS upgrade? A custom made low comp piston?

I'm just curious if these bikes are handling boost ok or do they need internal mods to be ok. I was informed after the failure that I should've increased the piston ring gaps. Valve clearancestors were perfect, no signs of detonation, bottom end held up but piston had a total meltdown.

 

[wwillf01]

Heat from running lean with fueling issues? Did you run an Afr gauge?

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[wwillf01]

Also didn't they recommend 110?

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[wwillf01]

On mine during the tuning process on the dyno the pump went.. now it still worked but it would start going super lean and just would not give enough fuel... Something to check

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[4strokesnewbie]

I used an AFR gauge. I saw no signs of running lean on the plug either. I'm not saying that it didn't at some point in the power curve run lean though.

 

[wwillf01]

Does boondocker have a way to look at the last ride you took and pull up the info on a computer? I will let you know how my kms set up goes... Will be out next week... But I did modify my engine quite a bit...

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[J&L Snowhawk]

Do the kms upgrade at just get there turbo. His stuff pulls like a train. Very good stuff. Boondockers needs serious help. Do head studs for sure

 

[4strokesnewbie]

Do the kms upgrade at just get there turbo. His stuff pulls like a train. Very good stuff. Boondockers needs serious help. Do head studs for sure

Any idea what the KMS upgrade includes? They have head bolts. Would you replace the bolts with studs? I'm not quite ready to give up on the turbo.

 

[4strokesnewbie]

Any idea what the KMS upgrade includes? They have head bolts. Would you replace the bolts with studs? I'm not quite ready to give up on the turbo.

I . .

 

[AK1000]

Only put 40 hours or so on my boondocker setup but had no issues with bone stock motor. Are you running the crap out of it? Also do you have the higher rpm tuned cdi? It seemed to be a richer tune with the higher rpm cdi and my afg was always a tad rich when I looked down on longer pulls.
I did add a couple points top end rpm, 8k and 10k and ran a nasty 110 plus home brew fuel. Always wanted to be sure I was not getting any detonation. Id look at a low comp. piston and head studs if you are already there. I thought the kms extra was intake plennum and turbo upgrade?
Not sure.

 

[tillbuilt]

I have put 54hrs. on a 2015 Yamaha YZ450F with a KMS turbo with NO issues.

I tune for 12.5 ARF and run AV gas at 9,000 - 12,000' of elevation, breathing 11psi of boost.

I set the ring gap at the open end of the factory setting and run stock 12:1 piston with KMS head studs.

This bike currently has less than 3% leak down and I will not be doing a top end this season. I will check leak down again at the end of the season and make the top end rebuild call then.

Bikes live on boost!!!!! it just has to be tuned correctly. NO TURBO is a BOLT ON and GO. It takes a season of conservative riding and tuning to be able to lay on the pipe and give it the gusto with out worry.

The bike I speak of is Batman and it is for sale. I will not give it away because it is probably the most reliable and best running turbo bike out there. When they are built right they live!!!!!

 

[ridgeclimber]

turboed snowbike

I am not that familiar with turboed snowbikes but I have ran my boondocker turboed sled for years. In my opinion boondocker make one of the best kits out there. All the hard parts for the kits are similiar. What sets boondocker apart from the rest in my opionion is their control box. Any turbo kit is only as good as the tuner. What elevation do you run at. That make a big difference. If you unload at low elevation and it is not set up right you will cook it. You need a egt gauge to set it up correctly. That is all your worried about is how hot is that cylinder temp. The af gauges fowl up and are slow to read with the race fuel. They don't last long. 8 psi of boost should hurt things. Also how is your air intake. If it is restricted or to hot of air going into the turbo that make a big difference in tuning. Also I used a intercooler aswell, to keep the charge air cooler just to be safe.