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Offline beaner

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KTM 105 SX
« on: June 23, 2017, 12:41:54 PM »
OK guys, it's a been some time since I've posted here. I know the site was down for a long time, I hope some of the regulars are still here.

So last year I bought a Husky WR300 as an experiment. I thought more power was more better, but the bike was just too much for me. WAY too much. So I sold it, and this year I  decided to go in a separate direction, and bought a KTM105 to use as my woods bike. During hare scrambles my Husky (2011 CR150) just feels too big in the tight woods, and after about 30 minutes, fighting it just tires me out. So I'm going in the other direction. Since I'm the size of a teenager, I'm 5'6"/145 I'm trying something completely different, and bought a 2011 SX105. After a few rides now I can say that I don't think I've ever been faster in the woods. I whip through the tight stuff like it's nothing, and can do it lap after lap.

So I'm working on the suspension, ordered a Fatty pipe for it, but I'm wondering if anybody here has any tips, experience, or ideas on how to make this bike work a little better for the woods, or just more power overall? I don't really need any more power, it's actually more than fast enough for me in the woods, but could use a little more for the MX sections.

Hoping some here have experience with these bikes.
Ontario, Canada

Offline rsmith

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Re: KTM 105 SX
« Reply #1 on: June 24, 2017, 04:18:59 PM »
I don't have any insight for you on your 105 but I would like to say: Welcome back!

--Ron.

Offline Coop

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Re: KTM 105 SX
« Reply #2 on: June 25, 2017, 12:51:05 PM »
Welcome back. Sounds like a fun little bike.
- Mike - Don't take life so seriously, nobody gets out alive.

Offline eprovenzano

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Re: KTM 105 SX
« Reply #3 on: June 29, 2017, 05:24:39 AM »
Welcome Back

Not knowing much about the 105, I'd look at gearing options.  Are you looking for a little more bottom end?
Eric Provenzano
2019 KTM 300 XCW TPI
2000 KTM 300 EXC (Son's)
2001 KTM 380 EXC
Sold 1991 KDX 200... fun play bike
Sold 1999 KX250
Sold 1999 YZ125 (son's)
Sold 2001 Yamaha TTL 125 (son's 1st bike)
Sold but never forgotten 1974 Honda Elsinore CR250M
Sold 1974 Honda Elsinore CR125

Offline beaner

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Re: KTM 105 SX
« Reply #4 on: June 30, 2017, 06:06:08 AM »
Bottom end? of course,  just wondered if anybody here had experience with these motors. I've done a fair bit of looking online, and there's almost no info on these bikes. I'm really surprised.

I'm going to do the same as I did with my Husky. clean up the ports, increase compression, correct the squish, and pipe it. It was worth a fair bit of power, and made the power much more linear. I have a Fatty pipe on the way, and already have a +2 tooth rear sprocket. I figure +1 was my go-to, but since it's a smaller bike with less torque, +2 might be more better.

Will keep you posted.
Ontario, Canada

Offline Coop

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Re: KTM 105 SX
« Reply #5 on: June 30, 2017, 08:10:53 AM »
I remembered I rode with a guy a few times that had one of these about 5 years ago. He is about your size. I went back to his thread about it on the old PA dual sport site I am on and this is what he posted:

"It was used for GNCC riding, so it was set up really nicely for woods.   

112 cc stroker crank. 
MX tech suspension
Titanium rear spring
FMF SST header
FMF Titanium muffler
Rekluse z-start pro auto clutch 
Bar risers

Ran great at all RPM / throttle combinations. "
- Mike - Don't take life so seriously, nobody gets out alive.

Offline eprovenzano

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Re: KTM 105 SX
« Reply #6 on: June 30, 2017, 12:00:56 PM »
Look into adjusting the power valve tensioner and experimenting with different springs.   You should be able to dial the power to your liking and style
Eric Provenzano
2019 KTM 300 XCW TPI
2000 KTM 300 EXC (Son's)
2001 KTM 380 EXC
Sold 1991 KDX 200... fun play bike
Sold 1999 KX250
Sold 1999 YZ125 (son's)
Sold 2001 Yamaha TTL 125 (son's 1st bike)
Sold but never forgotten 1974 Honda Elsinore CR250M
Sold 1974 Honda Elsinore CR125

Offline beaner

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Re: KTM 105 SX
« Reply #7 on: July 18, 2017, 06:43:45 PM »
Fatty installed and +2 rear sprocket are on. I machined up a pair of bar risers and an adapter to run a spare husky 5.0 spring, and it's Much better. The gearing helped a lot, but the power and is a still a little in the twitchy side. Have to get in there and see how to adjust it. That will have to wait until after vacation.
Ontario, Canada

Offline beaner

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Re: KTM 105 SX
« Reply #8 on: October 11, 2017, 10:56:44 AM »
So although I hardly rode this year (extended vacation, lot's to do around a house) I still got a good feel for how this bike is going to work for me. A few times at the club property I rode with guys I didn't know, good woods riders, and I smoked them all on the 105  ;D They were embarrassed, you could tell. So I took my wife to the track, ran laps on the Husky, then the 105, and in the woods I'm significantly faster on the 105. So I just have to decide at this point if I want to keep this one (It's a high hour bike I got cheap) or look for a newer, cleaner one. Would be nice to have one of the new Husky TC's, but they're a little out of my price comfort level right now.

At least I have a project for the winter, that's the main thing
Ontario, Canada

Offline eprovenzano

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Re: KTM 105 SX
« Reply #9 on: October 13, 2017, 04:49:14 AM »
Glad to hear you're getting the 105 sorted out...  Nothing like setting up a bike to suit your riding style.   :)
Eric Provenzano
2019 KTM 300 XCW TPI
2000 KTM 300 EXC (Son's)
2001 KTM 380 EXC
Sold 1991 KDX 200... fun play bike
Sold 1999 KX250
Sold 1999 YZ125 (son's)
Sold 2001 Yamaha TTL 125 (son's 1st bike)
Sold but never forgotten 1974 Honda Elsinore CR250M
Sold 1974 Honda Elsinore CR125

Offline beaner

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Re: KTM 105 SX
« Reply #10 on: October 26, 2017, 03:48:06 PM »
So I've decided to start looking for a KX100. Prices are really coming down on the 2014+ bikes and apparently the upgrade in 14 was significant, and they are well known for good (for a small bike) bottom end power. They're a lot cheaper and easier to mod too.

Looking for any KX100 info/advice if it's out there
Ontario, Canada