58 replies to this topic

[FRECNDY TT Bronze Member]

An '04 YZ450 lever from fleabay arrived tonight. The good news is, CaptDan is right, it slips right onto the '99 kick shaft. However, I held it up against the 250, and I'm not sure I'll end up using it. It's a little longer and the tip goes a little farther forward than the stock kicker. That's not a problem with the stock tank. I don't know how it would work with a Zip-Ty or other desert tank.

The thing that concerns me more is the end of it bends away from the bike, so it sticks out and could catch on pants or boot, or even the ground, etc. in a crash. I'll mess with it more on the weekend, take some pics when there's light. I'd rather be without a starter than impaled on one.

[s14 2510s TT Silver Member]

I got a rigth clutch case half of a 99 for $25 shipped. kick shaft off an 00 $20 shipped. newer looking kick lever off an 05 wr 75 shipped. I spent more on the kick lever as I didnt want a real sloppy wore out one. I should olney have 120 into it so thats not too bad.

Edited by s14 2510s, 09 February 2012 - 06:09 AM.

[s14 2510s TT Silver Member]

I compared the old and new case half. The OD on the seals for the kick shaft are the same. You could use a 01 seal on your 02^ case half and bore the hole out to the size of the 01 shaft if you dont want to soarce a 01 case half and replace the bearings/eals in it. I didnt pay much for my case half $25 shipped but I forgot I had ceramic bearings in my 05 case half and I dont realy want to pull them and put them in the other case half so I might just bore out my original case half to the size of the 01 kick shaft. I e-mailed bearing tech to see how much the 2 bearings would be to make new if there not much ill probly put new ceramic bearings in the 01 half and be set. I have a 01 yz426f and the lever off that fits on my bike fine with the stock tank. The swap will add about a pound to the bike unless the 05 kicker I ordered is much lighter then my 426 lever.

[espkul TT Member]

Is it possible to visually inspect if the axle is worn? and brake any time soon

[FRECNDY TT Bronze Member]

You could periodically take it out and crack check it using dye penetrant, magnaflux or some other standard technology. If you don't already have access to those methods, it's probably cheaper to just get the used parts and replace everything. A few people get warnings, where the bike gets harder and harder to kick, presumably because the shaft is cracking progressively and allowing an angle to create friction in the side cover. Other people have no warning at all.

If someone had access to a bunch of broken and unbroken shafts, it might be possible to hardness test them or otherwise inspect them and figure out a way to determine by non-destructive inspection if a given shaft is likely to break.

[espkul TT Member]

Hmm.. okay, thank you! I've around 150 hours on my smoker so I'll think I'm going to buy a replacement shaft (I considered buying the larger one, but too much parts had to be changed). I'm not abusing my kick so I reckon it will hold for a while.

Edited by espkul, 11 February 2012 - 10:14 AM.

[shagger TT Gold Member]

Can we sticky this thread? It seems at least as important as yellow plastic and number plate swaps.

[Miscreantt TT Newbie]

Agreed. Sticky and in the FAQ.

[BDubb106 TT Addict]

My question is, did the splines change on any of the 20mm shafts? or are they all the levers interchangable with the correct knuckle? Ive read the thread three times through and never found an answer unless Im just not seeing the obvious

Edited by BDubb106, 16 February 2012 - 09:47 PM.

[s14 2510s TT Silver Member]

I have all the parts to do the swap now including the new ceramic bearings I had to order. The olney thing I found so far that I dont like is the way the 05-09 yz450 kicker bends back out twords the last few inches of the lever. The yz426 kicker fits better but weighs twice as much as the 450 kickstarter. Im hopefully going to complete the swap later today.

Edited by s14 2510s, 17 February 2012 - 01:30 AM.

[CaptDan TT Titanium Member]

BDubb106, on 16 February 2012 - 09:44 PM, said:

My question is, did the splines change on any of the 20mm shafts? or are they all the levers interchangable with the correct knuckle?

Splines are generally a machining standard. Any splined 20mm shaft will have an industry-standard machined pattern, unless something special is requested.

Presumably, ANY kickstart lever with a 20mm splined hole will be interchangable with a Yamaha part.

[BDubb106 TT Addict]

Cool exactly the info I was looking for!

[FRECNDY TT Bronze Member]

Bought a YZ400 kick lever on fleabay last night.

Now if the armor for my Husky will just show up so I can take the YZ down for awhile (top end, maybe 265 depending on bore condition, WR gears, this).

[WR250_YZ250 TT Newbie]

I'm ready to pull the trigger on replacing the 2002 parts on my bike with 2001.
I only had one concern. Is the spring end of the kick axle the same size/diameter on both the 2001 and 2002?
I note that on that end of the shaft, the torsion spring is the same part number, but the Spring Guide is different.

If this end of the axle is the same diameter, then I believe the parts required would be:

2001 Kick Axle Assy 5CU-15601-01-00
2001 Cover, Crankcase #3 5CU-15431-00-00
2001 Oil Seal 93102-20484-00
2001 Kick Crank Assy 4EW-15620-02-00
All other parts from the 2002 should work except for the bolt and washer to attatch the kick cran assy.

I hope to have my hands on a 2001 Kick Axle Assy by the end of the week, so I can measure the diameters.

[honda19 TT Member]

Someone previously on the thread suggested boring out the center of the shaft in order to put a steel rod of the correct diameter inside then welding it in. This would make the hollow shaft solid. Has anybody tried this? Any reason why it would not work?

[espkul TT Member]

A shaft brakes because the moment of inertia is too low. In other words: It's the outer diameter which is of importance because the inertia increases with the (radius)^4. So, you can put anything you want in the middle, but it'll still brake unless it's made out of a material many many many times stronger than steel (you can forget any metals known to man). So to save weight, the shafts are hollow

So the result from changing from 20 to 18 mm (or what it is) is making the shaft able to only withstand 60 % of what the older shafts do

Edited by espkul, 22 February 2012 - 04:07 AM.

[s14 2510s TT Silver Member]

I found a bbr kick lever for a yz426 on ebay. After buying a 04^ kicker and test fitting it they dont fit the top of the lever curves back out. I own a yz426 also so I took the kick lever off that and I like the fit of the yz400/426 lever better. The olney downfall is the yz426 lever weighs a ton. I had seen this bbr lever for the 426 a long time ago and had to buy it after not wanting to put the heavy 426 lever on. I got it in the mail today too bad bbr dosnt make this style kicker any more.

[CaptDan TT Titanium Member]

s14 2510s, on 22 February 2012 - 05:44 AM, said:

I found a bbr kick lever for a yz426 on ebay.
I got it in the mail today too bad bbr dosnt make this style kicker any more.

Pics?

[Pincushion TT Addict]

I dropped off my side case off RB's yesterday and he's confident in machining the case to accept the pre-02 shaft. We also verified the pre-02 seal fits the post-01 case (just like s14 2510s mentioned).

I still haven't sourced a kickstart lever and now I'm confused....
Can I just ebay a yz400/426 kickstarter (lever & knuckle) and bolt it on? Or do I need to disassemble, and swap the 426 knuckle to the YZ250 kickstart lever?

My yz250 OEM kickstart is hammered, so I'd like to buy one kickstart asembly to replace the whole thing. Is that going to be the 400/426 kicker?

[joshua_inigo TT Silver Member]

Great info!

Thanks Frecndy!