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YZ450f KMS turbo build

CATSLEDMAN1

Well-known member
Premium Member
Nov 27, 2007
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Missoula, Montana
taking note

your post says you have a 2012 120 kit, if its stock , the keyway shafts will not take the power of your turbo, very short life for sprockets and shafts. You need to upgrade to splined shafts or later model kit with.
 
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Jan 28, 2019
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.. The only issue I had was it would kill the afr sensor every 40 hours or so

You wanna know how much time I just spent online trying to order a new OEM AFR sensor from just about every online parts retailer....:mad:
wasnt till I got home and looked that I figured it out...lol
 
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Jan 28, 2019
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your post says you have a 2012 120 kit, if its stock , the keyway shafts will not take the power of your turbo, very short life for sprockets and shafts. You need to upgrade to splined shafts or later model kit with.

:face-icon-small-fro just when I thought I had all the parts on hand and ready... but its the First time I hear anyone mentioning that, nor have read anywhere of someone breaking them.... i know it has the bearing upgrade, dont know if that included any shaft upgrades..
If I do need them, is there an upgrade kit? or just buy generic spline shafts and cut to length?
 
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Jan 28, 2019
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I officially dove into getting the kit install started today. yup its been just chilling there in the garage for the past month cuz to busy with other projects. Decided it was time if I wanted to get any spring turbo riding, temps hit 72F here in the valley today! snows melting!

3 more questions came up as I was working on it- does it use the stock fuel pump?
How do I adjust the boost PSI? I'm gonna guess its with that nut on the connecting link of wastegate and blow off valve?..
Since I want to add LED lights, using the baja harness, and according to what baja told me there is 60watts of power left for accessories after the FI system has used what it needs -on a stock bike, how much watts will get used up by all the turbo system electronics?
And from what I understand, in a stock setup, I shouldnt use up all 60 watts as it would fry the stator right? should leave a buffer of about 20%?
 
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:face-icon-small-fro The jackshaft sprocket and shaft appear to be pretty messed up, along with the bearings. So replacing all that with parts from a local industrial supply shop.
I have the double bearing upgrade, and Im replacing the shaft with a 1'' keyed shaft and proper bearings. The shaft is pretty worn, so cant get an exact measurement, but from what I could figure it appears to have bean a 25mm shaft that timbersled used. Can anyone verify that?

Does anyone have answers to the post above this one?
Are 02 sensors generic and all that matters is the thread size?
Uses stock fuel pump?
 

wwillf01

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Aug 12, 2012
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Heber Ut
Just take it to an auto parts store it is a common Bosch part..

Sent from my SM-G975U using Tapatalk
 
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Jan 28, 2019
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Anyone able to help me out with this lockout clutch problem:
after I torque down the spring bolts, same as on stock clutch, when I pull in the clutch the lever travels only like 1/2 way and feels like cable will rip if I try to go any further. It looks like the pressure plate hits the bottoms of those flyweights and it stops the clutch from completely disengaging... its not supposed to be like that right?...

20190320_213708.jpg 20190320_213658.jpg
 
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Dec 1, 2007
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Yes the stock fuel pump would work. I would run a twin air fuel tank filter. While you have it apart take the stock injector out of the throttle body and make sure it is clean.

Stock stator will work fine, just put your light on a switch and only use it when needed. The bike will be hard starting if the light is on during start up.

Looks like your lockout is installed correctly, You will just need to set the cable free play. You may need to use the secondary adjustor to get it within range.
 

CATSLEDMAN1

Well-known member
Premium Member
Nov 27, 2007
2,630
1,207
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75
Missoula, Montana
:face-icon-small-fro The jackshaft sprocket and shaft appear to be pretty messed up, along with the bearings. So replacing all that with parts from a local industrial supply shop.
I have the double bearing upgrade, and Im replacing the shaft with a 1'' keyed shaft and proper bearings. The shaft is pretty worn, so cant get an exact measurement, but from what I could figure it appears to have bean a 25mm shaft that timbersled used. Can anyone verify that?

Does anyone have answers to the post above this one?
Are 02 sensors generic and all that matters is the thread size?
Uses stock fuel pump?

In regards to the older shafts and sprockets.

TS kits use a 25 mm shaft just under an 1", so no replacements out there in general machine use, I have machined down 1" shafts and tried to outsource them, all a waste of time.

I wouldn't sweat getting the shafts and sprockets changed out as a first order of business, get your turbo running first. BUT for sure a FYI you need to be aware of.

. Originally TS had a kit and reasonably priced to convert to the newer splined shafts.

The only cost effective conversion now is to simply get with a TS parts person and buy the parts.

If you can only buy the driven shaft and not an assembly, not sure what Polaris is offering there, just buy the shaft and press your old sprockets on.
The brake disc is kind of a miserable situation if you try to replace it all. You really don't need to do that, but you will have to have a machine shop mill the key way for your disc brake ( so little stress on this keyway/key down one of the female spline grooves and with the old key you will never have a problem) . If you get to that situation, just pm me or and we can talk about that. You will have to make several spacers to complete the project, TS doesn't have all the correct parts, but if you are launching into a turbo project, a spacer better be very elementary.

I have converted a half dozen or so kits, from the first year on up, way better, quieter/safer/less maintenance, been a couple of years but about $400.
 
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Jan 28, 2019
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Yes the stock fuel pump would work. I would run a twin air fuel tank filter. While you have it apart take the stock injector out of the throttle body and make sure it is clean.

Stock stator will work fine, just put your light on a switch and only use it when needed. The bike will be hard starting if the light is on during start up.

Looks like your lockout is installed correctly, You will just need to set the cable free play. You may need to use the secondary adjustor to get it within range.

Thanks for the tips.

I knew that about the lights. I was trying to find out how much watts I have left to use for LED lighting, after all the turbo electronics have used up their share?
after the stock electronics have used up their share, there is 60watts left according to baja. Baja and others only make 40w headlight kits for this bike, because you dont want to be sucking 100% of the stators power or it will kill it, correct? So they leave 20w as a buffer.
With all the extra turbo electronics, I know I will have much less free watts left. But how many?

The pics I posted earlier had the bolt springs backed off far enough to allow the clutch to fully disengage. No clutch cable adjustments are needed with the install of a lockout. I made a diagram with explanations to better show my situation:

imageedit_6_3660987481_zpsrpzlpq51.png
 
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Jan 28, 2019
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In regards to the older shafts and sprockets.

TS kits use a 25 mm shaft just under an 1", so no replacements out there in general machine use, I have machined down 1" shafts and tried to outsource them, all a waste of time.

I wouldn't sweat getting the shafts and sprockets changed out as a first order of business, get your turbo running first. BUT for sure a FYI you need to be aware of.

. Originally TS had a kit and reasonably priced to convert to the newer splined shafts.

The only cost effective conversion now is to simply get with a TS parts person and buy the parts.

If you can only buy the driven shaft and not an assembly, not sure what Polaris is offering there, just buy the shaft and press your old sprockets on.
The brake disc is kind of a miserable situation if you try to replace it all. You really don't need to do that, but you will have to have a machine shop mill the key way for your disc brake ( so little stress on this keyway/key down one of the female spline grooves and with the old key you will never have a problem) . If you get to that situation, just pm me or and we can talk about that. You will have to make several spacers to complete the project, TS doesn't have all the correct parts, but if you are launching into a turbo project, a spacer better be very elementary.

I have converted a half dozen or so kits, from the first year on up, way better, quieter/safer/less maintenance, been a couple of years but about $400.


I had to get the sprocket changed out, the teeth were getting way to thin to ride even stock, I know for sure it would not last a day turboed! I'll upload a pic of the old sprocket tonight. After pulling the sprocket and seeing the condition of the shaft, I knew it wont hold for long either.
Seeing the prices of timbersled parts, the limited availability of anything in 25mm, +shipping cost and wait times, I upgraded the whole jackshaft and bearing assembly for a 1'' and got all the parts in town at a local industrial supply store. Its a way better setup as now if something goes out I can walk into autozone and get a new 1'' bearing.
I got a 36'' keyed 1045 shaft, a hardened tooth #50 sprocket, and bearings for $150 And I still have 29'' of shafting left for another rebuild or project, and I think thats still less than what I would have paid timbersled.

Drilled and tapped the shaft ends for a slightly smaller OD bolt than stock, to give it more meat as the sprocket rides on the very end of the shaft. Used the same bolt on the brake side.
The # 50 sprocket has a much wider hub so it should last longer with less wear on the shaft/keyway. But its also much wider at the teeth, so I ground it down on the lathe with an angle grinder- my carbide wouldnt take those hardened teeth.
20190322_194752_zpsknl21wxq.jpg



The wider hub also bumped up against the bearing housing, so I took some material off for clearance, and filled in that pocket with grease for extra water protection :face-icon-small-win there is still a 1/8'' brass bushing/spacer between the sprocket and bearing inner race.
20190323_235338_zpsq2jccytr.jpg



For the brake hub I just opened it up a bit on the lathe to fit on the 1'' shaft, and same thing on the spacer. When the rotor goes out I'll just replace it with an SAE setup- proper spacing is critical there.
On the sprocket side, for some unknown reason, the spacer was hardened steel!:confused: .... couldnt turn it on the lathe so making another spacer...
20190323_233827_zpsaotdjvly.jpg



I also went up 1 tooth on engine sprocket and down 1 tooth on jackshaft sprocket. I'll post updates on how it pulls when I hopefully take it for a ride this weekend.

If this keyed shaft setup doesnt hold out to turbo power- like someone had mentioned earlier, then next rebuild will be with a splined shaft.
 
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How do I adjust the turbo boost? loosen the jam nut and spin the rod that goes into the turbo? or will that rip the diaphragm/ valve inside? So then I have to undo the wastegate linkage and spin that piece while holding the piece that goes into the valve?
20190323_235429_zpszurcnvkl.jpg
 
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Jan 28, 2019
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Need some help with the electrical harness and stuff:
There is a set of plugs on the turbo system harrness that plugs into the stock harness at 2 different locations (has the same plug). first location is into the ignition coil, and the other location is into the harness coming out of the stator. Which location is it supposed to be plugged into?
pic2_zps5ruorrj4.jpg
 
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Jan 28, 2019
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There are 2 plugs coming from the wideband to which I did not find a matching plug on the stock harness. Are those 2 the optional plugs and are not used?
pic3_zpshb0zjgbd.jpg
 
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