Turboed snowbike
- Thread starter wwillf01
- Start date
Have currently ridden about 80 hrs. Bike was brand new when the turbo was installed.
60 hrs 7,25 psi and 20 hrs 10 psi of boost.
No rebuild yet. Clutch and tranny seems to handle the power. Knock on wood...
Low comp piston was installed at 60 hrs.
Only issue to solve is that head gasket blows after a half winter season depite heavier studs. Solution is on the drawingboard...
I'm feeling pretty confident that the engine will last longer than predicted.
I think oil change every 10 hrs and race fuel will prevent breakdown.
Don't reach for 100+ hp figures. 85-95 hp is good enough and will benefit the longjevity of your engine.
Keep your eye on not over reving. Not easy when so much power but I think there's a high risk of blowing engine when continuasely hitting the limiter.
My bike is a 2012 KTM 500 EXC.
Home built turbo kit.
60 hrs 7,25 psi and 20 hrs 10 psi of boost.
No rebuild yet. Clutch and tranny seems to handle the power. Knock on wood...
Low comp piston was installed at 60 hrs.
Only issue to solve is that head gasket blows after a half winter season depite heavier studs. Solution is on the drawingboard...
I'm feeling pretty confident that the engine will last longer than predicted.
I think oil change every 10 hrs and race fuel will prevent breakdown.
Don't reach for 100+ hp figures. 85-95 hp is good enough and will benefit the longjevity of your engine.
Keep your eye on not over reving. Not easy when so much power but I think there's a high risk of blowing engine when continuasely hitting the limiter.
My bike is a 2012 KTM 500 EXC.
Home built turbo kit.
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Havent heard of any head gasket issues on production turbo kits. Maybe bad luck for me as a home builder or they have a good solution in solving this problem.
Not a lot of turbo bikes out there and maybe owners/builders is not open about improvements or problems?
The low comp piston was installed in order to safely raise boost to 10 psi with race fuel.
In retrospect I would go for standard compresion. Race fuel is required in this setup.
You hardly doesn't feel any difference between 7,25 or 10 psi.
At least that was what I felt on the 500. Smaller displacement, high reving engines, maybe is different like a 450.
Haven't tested a Rekluse on a Turbo. Does it hold up?
I ride with standard clutch with double clutch springs. That works very well and is slightly harder to engage.
Not a lot of turbo bikes out there and maybe owners/builders is not open about improvements or problems?
The low comp piston was installed in order to safely raise boost to 10 psi with race fuel.
In retrospect I would go for standard compresion. Race fuel is required in this setup.
You hardly doesn't feel any difference between 7,25 or 10 psi.
At least that was what I felt on the 500. Smaller displacement, high reving engines, maybe is different like a 450.
Haven't tested a Rekluse on a Turbo. Does it hold up?
I ride with standard clutch with double clutch springs. That works very well and is slightly harder to engage.
R
Rush44
Well-known member
So far the main weakness I keep talking to people about is the stock clutch. So far I count 3 smoked KX clutches and 1 that pretty much grenaded on it's first trip out.
Sweden is 100% right about keeping out of the limiter as much as possible, minding your oil and fuel, and also watching those temps on spring days. My buddies turbo had a lot of over-temp issues after April and is working on a track cooler setup kinda like what Sweden has going on.
Because of the issues with turbo (at this point, still in it's infancy) I've elected to go with a 20 shot of NOS until the turbo bugs are worked out by people with deeper pockets than me. NOS still has it's own drawbacks, but I believe they are more manageable for me.
Sweden is 100% right about keeping out of the limiter as much as possible, minding your oil and fuel, and also watching those temps on spring days. My buddies turbo had a lot of over-temp issues after April and is working on a track cooler setup kinda like what Sweden has going on.
Because of the issues with turbo (at this point, still in it's infancy) I've elected to go with a 20 shot of NOS until the turbo bugs are worked out by people with deeper pockets than me. NOS still has it's own drawbacks, but I believe they are more manageable for me.
Thank you for the info.... I have been going back and forth on a Turbo 4 stroke or just building up a 500 smoker to a 600ish big bore..... Now when you say a stock clutch if you went to something like a zstart pro type set up like the snowwest build on the wr do you know if that solved the issue (I was trying to find some thread on repairs needed over the winter)? I know with my sled turbos are a game changer for us at high altitude..... But on the flip side it sounds like there will be a solution for the carb icing on the smoker so I keep going back and forth
Its no fun blowing things up in the back country I will give it another year and ride my 300 and see what happens...Sent from my iPad using Tapatalk HD
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Our guys here have made a Agreement to not go Turbo and keep it fun for all and run non Turbo bikes. Les see who is the first one o beak the promise.
After riding the Demo Turbo and a 2014 YZ 450 my money is going toward a dedicated YZ 450 snow bike. It outperformed all other modded (non Turbo) snow bikes hands down . And that total stock as it comes from the showroom floor
After riding the Demo Turbo and a 2014 YZ 450 my money is going toward a dedicated YZ 450 snow bike. It outperformed all other modded (non Turbo) snow bikes hands down . And that total stock as it comes from the showroom floor
Turbo
I have a boosted yz 450 boondocker kit. Seems like the bike loves the turbo, i change my oil every ride and run vp fuel. I am currently running 12.7 lbs of boost. No issues have come up, i try to not over rev but i definately dont baby it.
Upgrading to rekluse clutch before snow flies. The bike is in the showroom at yamaha in sandpoint if you wanna check it out. NOT FOR SALE
I have a boosted yz 450 boondocker kit. Seems like the bike loves the turbo, i change my oil every ride and run vp fuel. I am currently running 12.7 lbs of boost. No issues have come up, i try to not over rev but i definately dont baby it.
Upgrading to rekluse clutch before snow flies. The bike is in the showroom at yamaha in sandpoint if you wanna check it out. NOT FOR SALE
R
Rush44
Well-known member
For all you guys wondering about a good manual clutch don't forget to check out Rekluse's Core Manual with Torq Drive. The auto clutch isn't for everyone but this manual clutch dramatically improves clamping force and would probably be the best option out there for a beefy manual with turbo. I hope to get this on a friends turbo for the winter since he just about smoked his this last spring.
Customer service and install help at Rekluse is second to none.
http://www.rekluse.com/torqdrive.shtml
Customer service and install help at Rekluse is second to none.
http://www.rekluse.com/torqdrive.shtml
I have a boosted yz 450 boondocker kit. Seems like the bike loves the turbo, i change my oil every ride and run vp fuel. I am currently running 12.7 lbs of boost. No issues have come up, i try to not over rev but i definately dont baby it.
Upgrading to rekluse clutch before snow flies. The bike is in the showroom at yamaha in sandpoint if you wanna check it out. NOT FOR SALE
What type of hours did you put on it?
Hours
I got about 25 rides in this year, maybe more, didnt keep track. I had to stop riding midway through march due to a bruised tailbone- cornice won. I didnt turbo it till midway through the season, not exactly sure but probably around 10 rides boosted. I talked with boondocker extensively before i bought the kit. They said they have been testing their turbo kits for two years and havent replaced a top end on any of their bikes.
I got about 25 rides in this year, maybe more, didnt keep track. I had to stop riding midway through march due to a bruised tailbone- cornice won. I didnt turbo it till midway through the season, not exactly sure but probably around 10 rides boosted. I talked with boondocker extensively before i bought the kit. They said they have been testing their turbo kits for two years and havent replaced a top end on any of their bikes.
So what type of hours are people getting before top ends.... Is it too much to ask to get 75 hours before a rebuild.... I am looking for someone who has put some time on these things?
After a full season on the Black Momba and 30 plus hours on a 2015 Yamaha YZ450F with a KMS turbo I can answer this question.
Exhaust valves at .014 and intakes at .023. Leakdown at 3%
I would say that there is no question this bike is happy being turboed.
This bike was rode hard and pushed to the limits, even winning the Big Dog event in every bike class. It was raced in snow cross, hill cross, hill climb, and BCRA events. It even pulled duty on family ride days.
I did have one bracket break and I had to repair that. I never cracked the motor until today to check its health.
I am looking forward to another great season not turning wrenches on this bike.
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They have the the brother bike to this one and have the Aerocharger installed. I will hopefully have it in the next few weeks after its tuned.
Love the idea of keeping more power at elevation. Heck, even at 75 or 80hp you are at twice the hp that a 55hp bike has at 10k feet (30% hp reduction). But I'm with Rush at this point; not wanting to lay out that kind of cash until better proven and, for me, maybe not even then. Will be watching to see how the nos systems pan out this year as that is likely a better fit for me anyway.
Quick sidebar question; do the turbos cut exhaust decibal noticeably or is it insignificant?
Quick sidebar question; do the turbos cut exhaust decibal noticeably or is it insignificant?
Haven't seen a Quiet turbo bike so far.
Seen many blown turbos from bouncing of the rev limiter.
Riding them is not nearly as much fun as you may think, you are either on the rev limiter or in the turbo lag. Rode with a guy with a turbo KTM and Yamaha never really found the awesomeness I know rom turbo sleds. Especially when boon docking in the trees. If you want to hillclimb with the sleds maybe
Seen many blown turbos from bouncing of the rev limiter.
Riding them is not nearly as much fun as you may think, you are either on the rev limiter or in the turbo lag. Rode with a guy with a turbo KTM and Yamaha never really found the awesomeness I know rom turbo sleds. Especially when boon docking in the trees. If you want to hillclimb with the sleds maybe
I have over 40 hours on a 2015 KTM 500 xc-w with a Boondockers turbo running at 13 lbs on av over 6000 ft(110 race below).
I change the oil (and filter) every 5 hrs with Motorex oil, and have had no engine problems whatsoever. Valves are still in spec and leakdown in spec. The only issues I have had are a stalled (ruined with no compensation) turbo ($900) at 30 hrs because Boondockers does not pull their oil from a filtered source (fixed with a $10 inline filter) and a rusted through exhaust outlet (they actually covered this one)because they are too cheap to build it out of stainless.
My clutch is stock with no issues, ridden by everyone including the inexperienced with no problems except the ones listed above.
I try to discourage everyone from going turbo because it is more fun watching them try to get to the top of the climb where I'm at
I change the oil (and filter) every 5 hrs with Motorex oil, and have had no engine problems whatsoever. Valves are still in spec and leakdown in spec. The only issues I have had are a stalled (ruined with no compensation) turbo ($900) at 30 hrs because Boondockers does not pull their oil from a filtered source (fixed with a $10 inline filter) and a rusted through exhaust outlet (they actually covered this one)because they are too cheap to build it out of stainless.
My clutch is stock with no issues, ridden by everyone including the inexperienced with no problems except the ones listed above.
I try to discourage everyone from going turbo because it is more fun watching them try to get to the top of the climb where I'm at
