Comming Soon
Home > Forum

Recent Posts

Pages: [1] 2 3 ... 10
General Two Stroke Talk / Re: KTM 105 SX
« Last post by Coop on June 25, 2017, 12:51:05 PM »
Welcome back. Sounds like a fun little bike.
Photos & Videos / Re: The Story of Maico Motorcycles (Documentary)
« Last post by Coop on June 25, 2017, 06:04:10 AM »
Hay man! Good stuff in TrailRider about that big Maico of yours :) .
General Two Stroke Talk / Re: KTM 105 SX
« Last post by rsmith 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!

General Two Stroke Talk / KTM 105 SX
« Last post by beaner 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.
General Two Stroke Talk / Re: Good, Bad and the Ugly of 125's?
« Last post by beaner on June 23, 2017, 12:25:41 PM »
I wish I'd seen this before, I would have pointed you in another direction.

I raced an 04 RM125 for about 5 years, then bought a 2011 Husky CR. Within a few weeks I went from being a midpack rider to winning races and by the end of the year, won the division.

Suspension every bit as good as the YZ (exactly the same forks),  way better handling than the RM, and loads of potential with that motor. The Italian Husky two stroke is definitely an underrated bike.
Vintage Two Strokes / Re: 1986 CR250 Build
« Last post by racer x on June 21, 2017, 05:44:07 PM »
General Two Stroke Talk / Re: Transfer Port Injection
« Last post by Flettner on June 21, 2017, 01:34:23 PM »
Yes a large (burly) injector is needed because at some stage injection is taking place under compression. At higher speeds there is just not the time to inject and mix all the fuel with all the air, thats where Diesel comes unstuck. Cant process the injection and burn at high engine speeds, thats why they react so well to over boosting with air (turbo)but there is a time limit and thats why you don't see diesels doing 13000 rpm. Apart from the general size Im just talking burn wise. This is where HCCI has a major benefit, all air and fuel is already mixed so its just a matter of compressing it at the right time for combustion (controlled detonation). Hence my HCCI test engine, sown here already? Another project in itself. Yes sorry, we have talked about this already.

General Two Stroke Talk / Re: Transfer Port Injection
« Last post by rsmith on June 20, 2017, 07:41:00 PM »
Interesting, I always assumed the DI system to be more like a diesel system where the injection cycle happens very late in the power stroke hence the need for a burly injector to overcome the compression.

Vintage Two Strokes / 1986 CR250 Build
« Last post by rsmith on June 19, 2017, 08:34:27 PM »
A very (very) long time ago I was given an 86 CR250 that needed a crank.

It's under a tarp in the back yard but I just found a nice looking crank for it on eBay so, just maybe this may live again sometime soon.

I'll post it up as I go.

General Two Stroke Talk / Re: Transfer Port Injection
« Last post by Flettner on June 19, 2017, 04:37:10 PM »
Is Direct Injection the future?
It seems the DI Rotax sled engines now run injectors at the inlet port that fire once the pipe is 'on'. makes a bit of a mockery of DI. DI also has to start injecting before the exhaust port is closed as the revs increase, once again making a mockery of DI.
This TPI isn't as bad as everyone would have it (know it alls on the internet) with the gas dynamics in a twostroke its the lower end power (rpm) where the short circuiting takes place (hence DI systems not being pure DI up in the revs only low down), its the position and late firing of the B port injectors that save the day for TPI. This is where most fuel is lost to the exhaust on a carburetor engine and lets face it, where we ride our bikes most, off the pipe or at least in transition.
The real answer is to keep the transfer gas speed up at lower RPMs and lower the port timings (including exhaust port) in conjunction with a modified TPI system. Sliding cylinder anyone?Cylinder could do the throttling (power controlling) while the inlet would have no throttle body, just straight in through the reeds, so the crank case would always be under pressure. Always a good, high inertia, gas flow into the cylinder under an amount of control. This system would require my new TPI system to operate.  Results would show a very wide torque curve and excellent fuel economy.

Pages: [1] 2 3 ... 10