2017 ktm 150 light weight build

Pro pegs Ti Brake tip.
Pro pegs mud version
Motion pro wheel locks
motostuff rotors(had ti rotors but didn't like them)
arc melon levers
Think seat cover & bar pad


warp 9 makes the axles & pivot the cheapest I've seen.

DTR830 wrote:

Pro pegs Ti Brake tip.
Pro pegs mud version
Motion pro wheel locks
motostuff rotors(had ti rotors but didn't like them)
arc melon levers
Think seat cover & bar pad


warp 9 makes the axles & pivot the cheapest I've seen.

That’s pretty much the route I’ve been looking to go.

Please do a before and after weight comparison.

BobPA wrote:

Please do a before and after weight comparison.

It’s a little late for that as I lve already started reassembling.

What chain will run? I’ve had good luck with the rk mxu that pc uses. I’m not sure if it’s the lightest but it looks tiny.

byronf29 wrote:

What chain will run? I’ve had good luck with the rk mxu that pc uses. I’m not sure if it’s the lightest but it looks tiny.

D.I.D gold. I’ve had good luck with it. I’ll stick to certain things that has worked well for me in the past.

byronf29 wrote:

What chain will run? I’ve had good luck with the rk mxu that pc uses. I’m not sure if it’s the lightest but it looks tiny.

CrGuy2T wrote:

D.I.D gold. I’ve had good luck with it. I’ll stick to certain things that has worked well for me in the past.

DID Golds are great, but the Sunstar MXR1 chain is a bit lighter; we've had great luck with them on both our 450's and 125 projects.


WPS distributers can get you DRC aluminum bolts, which are lighter than Ti, for low-torque areas like fork guards, certain fenders, case savers, perches, etc.

https://www.ebay.com/itm/Aluminum-Flange-Bolts-Ti-Color-M6X12mm-20-Pk-DRC-D58-51-912/401514338614?epid=2288354536&hash=item5d7c1e9936%3Ag%3AEQcAAOSwi4davB66&_sacat=0&_nkw=drc+aluminum+flange+bolts+m6x12&_from=R40&rt=nc&LH_TitleDesc=0


Don't forget the lightest tubes you can get away with (IRC cheapies for me) and tire combos: Pirelli MXMS and the new Michelin's are supposedly some of the best at the moment in this regard?


Ps: The PHDS mounts are nice in action, but heavy on the scale! Better off with OE 1.125" mounts and Pro Taper EVO bars (no crossbar) if weight is priority numero uno

crc245 wrote:

DID Golds are great, but the Sunstar MXR1 chain is a bit lighter; we've had great luck with them on both our 450's and 125 projects.


WPS distributers can get you DRC aluminum bolts, which are lighter than Ti, for low-torque areas like fork guards, certain fenders, case savers, perches, etc.

https://www.ebay.com/itm/Aluminum-Flange-Bolts-Ti-Color-M6X12mm-20-Pk-DRC-D58-51-912/401514338614?epid=2288354536&hash=item5d7c1e9936%3Ag%3AEQcAAOSwi4davB66&_sacat=0&_nkw=drc+aluminum+flange+bolts+m6x12&_from=R40&rt=nc&LH_TitleDesc=0


Don't forget the lightest tubes you can get away with (IRC cheapies for me) and tire combos: Pirelli MXMS and the new Michelin's are supposedly some of the best at the moment in this regard?


Ps: The PHDS mounts are nice in action, but heavy on the scale! Better off with OE 1.125" mounts and Pro Taper EVO bars (no crossbar) if weight is priority numero uno

There are some areas on not going to mess with. I have thought about going back to stock barnlubts as I like solid mounts. I was just swapping everything from one bike to the other. I’ll start changing and switch bolts as they come in.

no more funner bike than a light weight small cc 2 t.

thats going to be trick!

i've just sold my lightened kdx220, every possible bracket/lug off, 200 bottom end(much smaller ignition set up), kx 125 bits and peices, light tyres tubes, au bolts everywhere, etc (moving home) and boy do i miss that bike, i could litereally shove it into any line at any time.

This is going to be a sweet project!

I’m got to ride it today. We shall see how well the aer cones work.

Did the AER cones cost more than the original bike?

Helder wrote:

Did the AER cones cost more than the original bike?

No I found a good used set. They seemed to work pretty good on a smaller track. I’ll try again next weekend on a track with some rust and braking bumps. They worked better than I expected, time will only tell.

That bike is already light so this thing will be super fun when you are done!

The RK MKU is a nice chain but it is an o ring if I remember correctly. I’ve never tried the Sunstar MXR1. For about the same price you can get, (my personal opinion) the lightest nicest chain I have seen the EK 520MXR 3D.... it looks like jewelry ?

https://goo.gl/images/KTzwRU

Ti axles & linkage bolts best bang for your buck along with Aluminum bolts on the non critical parts. Then with whatever $$$ left over sprinkle in your Ti hex bolts & nuts where you like :-)

Do they make a Ti rear spring for that shock? I’m sure someone must.

PC carbon / Ti shorty is the way to go for silencer.

Lightweight tube for rear & fat tire mtb tube for front.

Pirelli for tires.

Light weight seat foam if you don’t spend a lot of time in the saddle... LoL

Helder wrote:

Did the AER cones cost more than the original bike?

CrGuy2T wrote:

No I found a good used set. They seemed to work pretty good on a smaller track. I’ll try again next weekend on a track with some rust and braking bumps. They worked better than I expected, time will only tell.

Did Powerband revalve them for you or was that the previous owner? Powerband worked wonders on my 4CS and AER setups.

I believe the sun star chain was the lightest in the class. I want to say talon sprockets as well. Pirelli is the lightest tire. You could always do a dry weight after and compare it to the stock numbers. I understand Ti for the axels and stress bolts but what about using aluminum bolts for the rest

Helder wrote:

Did the AER cones cost more than the original bike?

CrGuy2T wrote:

No I found a good used set. They seemed to work pretty good on a smaller track. I’ll try again next weekend on a track with some rust and braking bumps. They worked better than I expected, time will only tell.

Rickyisms wrote:

Did Powerband revalve them for you or was that the previous owner? Powerband worked wonders on my 4CS and AER setups.

Yeah billy set them up. I have some spring forks from him too. His stuff is really good.

I’m trying to do it as light weight as I can without splitting hairs. The graphics are gonna add about a 1.5 lbs maybe more. I was able to get the seat foam installed and as many ti bolts as my stash drawer would let me. There is probably atleast a pound of plastic inside the air box for the battery tray and stuff. I’m going to work on removing all that soon. I am just waiting on more pieces to come in as I’m ordering what I don’t have.

What's the stocker Ktm weigh?
I just weighed my modded Cr and it was 90kg. But my tyres are heavy so will be 89kg soon. It's just so much lighter than my 450 I actually laughed when I first rode it.

CrGuy2T wrote:

I’m trying to do it as light weight as I can without splitting hairs. The graphics are gonna add about a 1.5 lbs maybe more. I was able to get the seat foam installed and as many ti bolts as my stash drawer would let me. There is probably atleast a pound of plastic inside the air box for the battery tray and stuff. I’m going to work on removing all that soon. I am just waiting on more pieces to come in as I’m ordering what I don’t have.

I have a 17 Ktm 150sx , I cut the inside cdi holder right behind the last bolt allowed bike to breathe much better while still keeping the cdi secured , and cut the inside wing on the air box cover that snaps on wasnt worried about weight with this but definately helped.

you can use aluminum bolts and screws in low stress areas like the side covers. starcross tires are lighter than most others. custom made 7068 aluminum axles if you can't get the ti ones, 7068 aluminum spacers, and swing arm bolt.

I’m not tonsure about aluminum axles. I did manage to use a silencer off my 03 kx. It’s an old factory one and saved over 2lbs. It actually fit near perfect.

Barnett468 - can you show me a reputable company (like racetech for example) that makes 7068 aluminum axles for KTM, YZ’s CR’s etc? I would be willing to bet there are not very many (or any perhaps but I could be wrong) & there is a reason for that... My guess is the probably due to the fact that steel alloys have what is termed a "fatigue limit," which means that when loaded below that limit, it lasts essentially forever. Most aluminum alloys lack such a fatigue limit, so they accumulate fatigue damage steadily under stress cycling. This is why airframes, wings, etc. have a "lifetime" or service limit. Notice that the landing gear of commercial aircraft is made of forged steel I believe. In addition aluminum is 1/3 the stiffness of steel based alloys no matter what alloy or heat-treat it may be. A very simple example could be If we put an equal size steel bar & an alum bar in a wall & start to hang equal weights on the ends of these bars the bars deflect elastically under the load. As we add load equally, that the aluminum bar is deflected three times as much as the steel. Finally, at some load, both bars yield. The initial elastic deflection is a measure of stiffness. The eventual yield is the measure of strength.The point to be made here is that strength and stiffness are separate qualities.

You need to understand aluminum completely before you judge it. You can most certainly use aluminum axles safely in many apps IF you use the proper type of aluminum. I have done it and some people running the newer bikes in recreational road racing have aluminum axles, however, they are running 7075 aluminum and I use 7068 aluminum which is much stronger, and both of these grades of aluminum are much stronger than 6061.

"Most aluminum alloys lack such a fatigue limit, so they accumulate fatigue damage steadily under stress cycling. This is why airframes, wings, etc. have a "lifetime" or service limit."

Yes, aluminum has a fatigue limit, however, you will likely be dead and buried long before an aluminum axle reaches that limit in this type of application. Kaiser aluminum does fatigue tests on their aluminum and the test on the 7075 is ten million cycles. Also lot of force must also be applied to aluminum before it appreciably contributes to the fatigue of the metal, and this force is fairly high. For example, if you bolt the end of a 1" round bar of aluminum to a vice, leaving 12" of the bar exposed, then apply 1 lb of force to the exposed end of the bar and do it a bazillion times, the axle will still not have fatigued enough to fail. The greater the force applied, the sooner a failure will occur.

You also state that airplanes are made of aluminum, and my guess is that you have flown in one before, and that if you did, I'm also guessing that you didn't worry about how many fatigue cycles it had been through, but I could be wrong. Irregardless, I for one would much rather have a part break from fatigue when I drop from 10 feet in the air instead of when I drop from 35,000 feet in the air.

7068 aluminum is also much stronger than what aviation typically uses, although all aluminum still has a fatigue limit.

There are also cars that have aluminum frames. The 2013 and earlier BMW M6 is one of them, plus, many motorcycles, including many motocross bikes have aluminum frames and aluminum swing arms and aluminum handlebars, and aluminum engines, aluminum wheels and aluminum sprockets etc, yet people don't seem to be concerned about these parts breaking in half from fatigue.

They have also been making connecting rods and rocker arms out of aluminum for racing engines for around 40 years, and many street racers have over 100,000 miles on their rods and rocker arms.

Steel can and does also occasionally fail. I had many steel motocross bike frames develop cracks and also cracked many when I worked in the R & D department of Kawasaki Motors.

If one is concerned about an aluminum axle reaching its fatigue limit and failing, they can simply replace it periodically, like after every 5,000 hours of riding etc.

Axles can also be made out of "Giga steel" (alumasteel) but that is not easy to obtain at this time.

CrGuy2T wrote:

I’m not tonsure about aluminum axles. I did manage to use a silencer off my 03 kx. It’s an old factory one and saved over 2lbs. It actually fit near perfect.

I like your scale. I need to get a new one. Could you please tell me anything about it like what is it's accuracy and what is the maximum it can weigh and what brand and model and where you bought it etc?

Thanks in advance for any help.

"Barnett468 - can you show me a reputable company (like racetech for example) that makes 7068 aluminum axles for KTM, YZ’s CR’s etc? I would be willing to bet there are not very many (or any perhaps but I could be wrong) & there is a reason for that..."

That question is actually irrelevant. There are very few companies making axles from titanium even though it is extremely strong and readily available and there is a reason for that also, however, below is a link to one company that currently makes aluminum axles and there are one or two others. The axles below are for drag race and road race bikes that go in excess of 130 mph with some bikes weighing maybe 40% more than many late model motocross bikes.

https://www.saeoutlawperformance.com/CBR-conversion-axle-for-GSXR-1000-ALUMINUM-CBCA102.htm




"In addition aluminum is 1/3 the stiffness of steel based alloys no matter what alloy or heat-treat it may be. A very simple example could be If we put an equal size steel bar & an alum bar in a wall & start to hang equal weights on the ends of these bars the bars deflect elastically under the load. As we add load equally, that the aluminum bar is deflected three times as much as the steel."

This is also irrelevant since all metals will in fact "bend" under a certain load. The thing that is relevant is simply designing the part in question so it will perform sufficiently for its intended use.