Custom Stems

Questions and comments about converting to beefier forks..
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

I will have to look at the two first, the KDX and the KX stems. I have access to pretty much every material including titanium. The cheapest and easiest to machine and ship is 6061 Al. i will conduct a hardness test on the two stems and see what material they have used, either way steel or aluminium will be no problem.
If aluminum, can be hollow or solid. I prefer solid aluminum for ease of manufacturing and stainless steel for shininess :grin: , what do you think?
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

Either should work since the stock KX is hollow aluminum and the KDX is hollow steel. What grades, I have no idea.

I also don't know why Ma Kaw chose the different materials for each and my mind would want to know before I fashioned any.

I feel you really can't go wrong with the steel though since it is definately stronger.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

How much torque on the stem nut again?
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

33ftlbs for the Steering Stem Head Nut.
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
T-Roy
Supporting Member III
Supporting Member III
Posts: 77
Joined: 03:14 pm Feb 04 2005
Country:
Location: Knoxville, TN
Contact:

Post by T-Roy »

Mike, any estimate on that TT shipping? I'm willing to help out on your shipping in order to get a tru-fit 03 stem. Let me know, I'm on it like white on rice. :cool:
2001 KDX 200
User avatar
Colorado Mike
Gold Member
Gold Member
Posts: 1921
Joined: 11:42 am Feb 25 2005
Country:
Location: Colorado

Post by Colorado Mike »

I went to UPS's website and punched in $30.00 as the customs value. It came back with $20.58 for the shipping charge. Does anybody know if the same charge would apply to get it back? I don't know if customs gets charged both ways. What was that NAFTA thing all about? I thought it was some kind of agreement. Something to do with free trade... somewhere around North America.. :roll: .
Mike

Life's tough, it's even tougher if you're stupid.
'04 KDX220
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

There is no customs fee coming into Canada for items that are not purchased. On the customs form, mark the value of sale at $0.00 and check off "gift". I think it is the same your way, i'll check it out. Check USPS, should be based on weight and size of package and type of shipping.

Duty is only charged on sales. For example, I send my carb to Ron, I get charged duty on the price of the mod, not the value of my carb.
User avatar
Colorado Mike
Gold Member
Gold Member
Posts: 1921
Joined: 11:42 am Feb 25 2005
Country:
Location: Colorado

Post by Colorado Mike »

cool. Maybe that total is just the shipping then. I thought the declared value question was for customs use. Anyway T-Roy, Phil wants me to wait until he does the one for his bike before I send mine. I'm not in much rush anyway with last week's -10° F temps. :blink:
Mike

Life's tough, it's even tougher if you're stupid.
'04 KDX220
User avatar
T-Roy
Supporting Member III
Supporting Member III
Posts: 77
Joined: 03:14 pm Feb 04 2005
Country:
Location: Knoxville, TN
Contact:

Post by T-Roy »

Sounds good guys, just let me know. I'm game for whatever works out. Thanks. :supz:
2001 KDX 200
IdahoCharley
Supporting Member II
Supporting Member II
Posts: 1005
Joined: 06:57 pm Mar 19 2005
Country:

Post by IdahoCharley »

FWIW - I've bought and sent a few things to/from Canada and Europe.

When sending items I've been request to mark either "Gift" with a value of less than $15 for reducing/elimination of taxes. When I've received stuff at least twice it has be marked "recycled scrapped salvaged metal parts" which were for beautiful aluminium machined big wheel rail extensions for snowmachines. I suppose there is some risk associated with "lost" items when doing it this way but you may need to weight the cost factor/chance factor into it.

P.S. I was also thinking the custom manufacturing of a stem could be a great idea. Getting custom stems for a variety of TT open up the KDX fork option possibilities. Seem like a lot of Yamaha forks and TT are normally available. Probably a whole new slew of problems to work out but isn't that half the fun??
KTM 380EXC Mine
KDX 200 Mark's
TTR 125 L Wife's
KDX 200 Austin's
EC 300 Tyson's
WR430 Husky - mine
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

"P.S. I was also thinking the custom manufacturing of a stem could be a great idea. Getting custom stems for a variety of TT open up the KDX fork option possibilities. Seem like a lot of Yamaha forks and TT are normally available. Probably a whole new slew of problems to work out but isn't that half the fun??"

SURE IS! I don't see it being too difficult unless the upper and lower TT clamps are either too close or too far from one another to incorporate a stem that fits the KDX. Even so, it would just make things more difficult. I prefer an all KAWI bike myself. :supz:
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

>|<>QBB<
Indawoods wrote:Either should work since the stock KX is hollow aluminum and the KDX is hollow steel. What grades, I have no idea.

I also don't know why Ma Kaw chose the different materials for each and my mind would want to know before I fashioned any.

I feel you really can't go wrong with the steel though since it is definately stronger.
I will have weigh the cost difference, keep in mind Aluminum is Canada's largest export, and I can get it dirt cheap, much cheaper than steel.

Although steel, Stainless or other could be an option for those wanting a more expensive stem.

I bet they chose the aluminum for the weight advantage. Although it is very minimal it all adds up, the same reason why the stem and axels are hollow. I dont believe that the material will have an effect on the performance of the part, there is very minimal forces applied to the stem once it is installed. My best guess at why they used steel for the KDX is that aluminum is very expensive in some countries.
User avatar
Indawoods
Creator and Founder
Creator and Founder
Posts: 9951
Joined: 09:59 am Jun 12 2003
Country:
Location: Midwest

Post by Indawoods »

It appears cost is the difference... (from a coupla post i have read) why a KDX stem is made out of steel. And it is not nessesarily stronger either from what I have read...

Here is an except:

"It's all dependant on wall thickness (if you have a hollow stem) and the type aluminum that you use. I'm sure that the KX stem has been engineered very near it's limit. Let's face it... the MX world is very competetive and every gram of weight that can be saved is. It makes perfect sense that they would not recommend reducing the stem diameter.

On the other hand... If you are fabricating your own stem from scratch. You can replace the mass that you removed from the outside of the stem to the inside bore by making it smaller. If you weren't concerned with weight you could make the stem from a solid aluminum bar.

My guess is that the KX stem is made from 6061-T6 a very good strong alloy with a yeild of 40,000psi and an ultimate of 45,000psi. You can just as easily obtain some 7075-T6 which has a yeild of 75,000psi and an ultimate of 85,000psi.

Just to give you an idea of just how strong aluminum is...

ASTM A-36 Steel has a yeild of around 36,000psi and an utimate of 58,000psi."



Not saying that any of it is true, just throwing it out there.....
*** Administrator //***
****'95 KDX 200/****

"People ate cows a thousand years ago for the same reason we eat them now. Cause they are easy to catch.We're not savages,we're just lazy. A cheetah could taste like chocolate heroin. But will never know. Those bastards are fast!!! "
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

Update-

Received my forks and TT today. I have taken a few rough measurements of the bore in the lower clamps. I have not pressed the stem out YET, so it is a little difficult to obtain an accurate meaurement but it appears as though the bore in my 05 KDX lower clamp and my 98 KX lower clamp are the same. I will verify this when I have pressed out the stem. Machining the stems looks to be a simple project but you never know.

It appears as thought the KDX wheel will fit. I am goiong to make a flexible bushing for the hex head side of the KDX axle (was originally on the right hand side of the OEM forks from sitting position, I will be moving this to the left side for spacer purposes) and a long nut with clearance for the shaft (like the 98 KX axel , check buykawasaki for details part 92015 & 92143A made in one piece). After assembling and ensuring the axel and caliper fits I will make a solid axel without the bushing.
The bushing will have a cutaway that will allow it to be clamped between the fork leg and fork holder and over the KDX axel. It will basically make the largest diameter portion of the axel that is clamped, bigger.

I start Christmas vacation tomorrow, so I wont have the luxury of using the machines for a bit. I will keep you updated.
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

Finished my prototype pieces in order to finalize the design of the axle. It works!
The 05 KDX wheel/spacer/odo fits with the 98' KX forks.
Green Hornet
Supporting Member II
Supporting Member II
Posts: 1455
Joined: 06:54 pm Aug 08 2005
Country:
Location: Orange County-New York
Contact:

Post by Green Hornet »

Sounds like a marketing item to me. Would have saved me $150 for the KX Wheel
"Growing Old is Mandatory, Growing Up is Optional"
2008 KLX450R
2008 DRZ400SM
2005 KDX 220R
1985 KDX 200A3
2005 KLX 125L (SONS)
2003 KTM 50SX Pro Jr
B Senior # 254/0092

http://sponsorhouse.loopd.com/Members/R ... fault.aspx
Thanks to my 2008 Sponsers:
Dunlop, SteelMX, Amsoil, Simpson, Pro Works Racing, Pro Moto Billet, SLAP Energy,Boyesen, Rhino Stands, SixSixOne/SunLine Moto for your support.
John W Read Jr
User avatar
KDXer
Supporting Member
Posts: 2845
Joined: 12:11 pm Nov 12 2004
Country:
Location: Sydney, Downunder

Post by KDXer »

$150 DAMN!!! :shock:

I paid $50US for an 02 wheel with virtually B/N rotor. Ouch...
Image

"I want to die peacefully in my sleep like my grandfather, not screaming in terror like the passengers in his car."
User avatar
canyncarvr
Gold Member
Gold Member
Posts: 6943
Joined: 01:07 pm Nov 05 2004
Country: US
Location: The Mythical State of Jefferson

Post by canyncarvr »

I understand the KX stem to be treated/coated in some way.

What are you going to use to keep the ODO housing from rotating? The KX fork doesn't have such a protrusion (I think).

The KX axle is a larger diameter. It's going to be a bit tough sliding the axle (larger) past the existing (smaller) 'hole'.

You have caps on your KX forks? Similar to the KDX cap on the RH side? My '99 KX forks don't have such caps. Caps would make it EASIER..but seems it would still be a problem with the larger 'inside' diameter axle.

Again...just curious.

Have fun with it!

Consider the source
Using a perceived level of knowledge to boost my self worth.
Non impediti ratione cogitationis

bike profile: !clicky!
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

I checked the KX stem, you're right, it is anodized resulting in a hard finish on the OD. Must be for durablility on the exposed section, less chance for oxidation and difficulty in changing bearing in the future. The section being pressed into the TT would be scraped off during pressing, guaranteed! I will iridite the the stem as an alternative, jsut like I will Iridite my upper fork tubes, more on that later.

The Odo bumps up against the fork leg, it doesnt appear to rotate too easily but could be a problem going in reverse :mrgreen:, if there was enough force on it going in reverse it could stress the cable i suppose. If there is a problem I will find a solution for it.

The KX axle is the same design concept as the 98 KX axle. the axle nut locates under the pinch clamp, same way the 98 KX does. The locating diameter on the 98 is larger on both ends than the axle diameter also. This is why the nut is screwd on afer the axle is placed through the hub, then torqued, then pinched under the clamps ( clamps on both sides).
User avatar
KDX220PHIL
Supporting Member I
Supporting Member I
Posts: 419
Joined: 08:31 am May 19 2005
Country:
Location: Nova Scotia, Canada

Post by KDX220PHIL »

The Odo is also a spacer and it has as likely a chance of rotating as your standard wheel spacers.

I did a hardness test on the kx stem, becasue it has been anodized it is much harder than normal aluminum, believe it or not, it is harder than the steel KDX stem but softer than a file!!! Another benefit to the anodized finish is its corrosion resistance, something you could only achieve with high grades of stainless.

I ended up pressing my KDX stem into the KX TT and as everyone said it was real easy, took nearly 15 tons to press it out and about 10 tons to press it into the KX TT. The stem came out easily exposing a beautiful finish on both the KDX TT and the stem, no chunks of aluminum. Machining the stem would still be no problem, however, you are not going to benefit from the hardness of steel or hardness and corrosion resistance of anodized aluminum. There could be possible problems with bearings becoming stuck to the aluminum and threads damaging easily, not to mention I do not know what will happen to a piece of standard aluminum when 15 tons is applied to it. Also, the steel bearing and uncoated aluminum are not normally a good match, this can cause a galvanic reaction and accelerate corrosion most likely causing the steel to stick to the aluminum. Iriditing does provide some corrosion resistance, but it does not offer hardness and the coating can be scratched off quite easily without a sealer. Down side of the selaer is that it is thick and very difficult to apply an accurate thickness.

The good news is that my setup does not require knurling or shims, one bushing for the top clamp does the trick. Easy as that!

Yes, I am disapointed, but not that bad. I am going to play around with this a little bit, still loooking for an easier solution. (It will be hard to get much easier). I will probably press that stem in and out a few times before too long, I am going to experiment with a few designs of stems and then try to find a resolution for the hardness and corrosion resistance problem. Half-tempted to set up some anodizing gear in my garage, I can think of many things I would love to have in that nice gold colour you see on all the new forks.

One thing worth mentioning and it has been mentioned before by many: you must tell the person who is pressing the stem out which way to press it out. Remember it must be pressed DOWN! Machinists do not have X-ray vision and unless they have worked with motorcycle clamps before, chances are they will not know.

Still working on the axle, waiting for an M14 x 1.5 Tap. I'll keep you updated.
Last edited by KDX220PHIL on 02:37 pm Dec 31 2005, edited 1 time in total.
Post Reply