KDXRIDER.NET

Hope this is the right place for this. I like the idea of the Hybrid, not sure I have the skills and sure don't have the tools to pull that off so was wondering if anyone has tried to put a aluminum sub frame on the kdx frame then do the kx fork mod. That would make the bike much lighter and would be much cheaper then doing the whole Hybrid thing. I got to thinking about this because as we where loading our bikes yesterday we noticed my kdx was quite a bit heaver the my buddies cr250 smoker.
So what do you think? klx125 sub frame?

I dont think the subframe is going to save enough weight vs the effort.

Weight reduction is only one of the reasons for doing a hybrid.

The sub frame is not removable on the KDX, and if you were to cut it off so that you could replace it with an aluminum version, I don't think you would shave more than a pound or two.

Yea, the subframe isn't removable. I'd think it would be easier and less work to do a hybrid, then it would be to make a custom sub-frame for a KDX

When comparing frame weights of aluminum vs steel framed offroad bikes, the difference is negligible. It takes much more material when using aluminum to achieve the strength and rigidity required, so the weight savings is just not there. Compare the size of the frame tubes on a KXF to those on a KDX and you will see what I mean.

2017 KX 250f - 233.6 lbs
2006 KDX 200 - 222.7 lbs

I feel like the weight distribution plays into it a good bit too. My hybrid feels like its at least 25 pounds lighter when I pull it off the stand, compared to pulling the KDX off the same stand. I think they only differ in weight by about 5 pounds or so, but it feels like its a lot more.

I could see that.

Ok, thanks for the replies. Guess I'll keep a eye out for a roller or a blown 125 this winter for a summer project. When I found this bike a guy had a 125 roller for sell on CL, he powder coated it pink and really didn't want much and all of a sudden had it posted for 2k. I don't see that anymore.
I did get a good ride on the bike yesterday 2nd real ride since rebuilding it and it actually handled pretty nice considering I haven't done anything to the shocks yet. My first ride was in the spring and the ground was dry so the bike just felt sketchy but yesterday the ground was perfect and the bike was a lot of fun.

Julien D wrote:2017 KX 250f - 233.6 lbs

That's a wet weight. (And Kawasaki says it's 229.9 : https://www.kawasaki.com/products/2017-KX250F)

barefootbob wrote:Ok, thanks for the replies. Guess I'll keep a eye out for a roller or a blown 125 this winter for a summer project. When I found this bike a guy had a 125 roller for sell on CL, he powder coated it pink and really didn't want much and all of a sudden had it posted for 2k. I don't see that anymore.
I did get a good ride on the bike yesterday 2nd real ride since rebuilding it and it actually handled pretty nice considering I haven't done anything to the shocks yet. My first ride was in the spring and the ground was dry so the bike just felt sketchy but yesterday the ground was perfect and the bike was a lot of fun.

If you will take the time to get your suspension set up correctly, correct spring rates and sag properly set, you'll probably find it handles well.

Jim B wrote:

Julien D wrote:2017 KX 250f - 233.6 lbs

That's a wet weight. (And Kawasaki says it's 229.9 : https://www.kawasaki.com/products/2017-KX250F)

Thanks. Doesn't really change my point though. Japanese manufacturers did not transition to aluminum frames with weight savings in mind. Also, I mis-typed there. Was supposed to be the dry weight for the 2016, not the 2017.

doakley wrote:...If you will take the time to get your suspension set up correctly, correct spring rates and sag properly set, you'll probably find it handles well.

That's some of the best money you can spend on the KDX, getting it sprung properly. Makes a world of difference.

If you ever want to feel HEAVY, pick up a KDX250 frame with rear supports mounted.

barefootbob where are you located? I have a 1999 kx 125 with no motor for sale. I'm in michigan

I'm in Northern Ca. I will get the bike sprung soon but last ride a couple weeks ago the bike really handled nice compared to the first ride last spring. Soil was perfect and as the day went on I got more familiar with the bike and was able to rip around pretty good. When we where loading up we noticed my friends CR250 was lighter so I thought that the hybrid would be lighter taking some of the load off the motor giving me a little more power. When I was rebuilding the bike I thought of doing a 250 kit but Ron @ RB Design was totally against that saying I would have over heating issues. I don't really ride in the summer but took his advice.