Speaking of speed... broke 83mph today...

[katoranger]

A honda offset key may be the trick. With more advance a higher octane fuel may be needed.

Allen

[fatboy250]

I am curious. Can't wait to see who will be the first to try it and see how much can be had from this type of easy mod. Keep us posted.

Jason

[knothead]

I won't touch the Lifan until I have my Yamaha running. I'm almost there, unless I need to adjust the valves (5 valves per cylinder, shim and bucket :evil: ), sync the carbs and put the bodywork back on. Even then I want to rule out everything I can before I open it up.

I didn't think about offset keys for bikes (duh!). Now I'm really wondering about the Honda keys. Man, I wish I knew if they are the same!

[mebigdave]

Just wondering if some thing like this would work?

http://www.jaycar.co.nz/productView....Max=&SUBCATID=

Programmable High Energy Ignition System


Refer Silicon Chip
This is Silicon Chip's most advanced and versatile ignition system yet and can be used on both two & four stroke engines. The system can be used simply to intercept and modify the factory ignition timing or turned into a stand alone ignition system with remapped timing, electronic coil control and anti-knock sensing. The unit will trigger from a range of sources including points, Hall effect sensors, optical sensors, or the 5 volt signal from the car's ECU. Timing can be mapped against engine load and RPM and adjusted in step as small as 0.5°.

Features:
> Timing retard & advance over a wide range
> Suitable for single coil systems
> Dwell adjustment
> Single or dual mapping ranges
> Two de-bounce settings
> Max & min RPM adjustment
> Suits 1 to 12 cylinder four stroke engines and 1 to 6 cylinder two stroke engines
> Optional knock sensing & correction

[IronFist]

Hey Knot.
Just wondering if the temperature has dropped where you are in the last couple days? Or if your sparkplug is looking a little lean? Just grasping at straws bro, you know I ain't a mechanic. :?

[pumpkin]

the last/only time i had my bike up to 80+ mph it was in the bed of my truck.lol.

[Thorgram]

I'm definatley going to be keeping an eye on this thread to see what happens if someone actually tries it. I'm all for tweaking, as long as it doesn't blow up that is.

[knothead]

Originally Posted by new2riding

Hey Knot.
Just wondering if the temperature has dropped where you are in the last couple days? Or if your sparkplug is looking a little lean? Just grasping at straws bro, you know I ain't a mechanic. :?

I thought about the temp and humidity, it's been unseasonally warm (low 70's) but I've rode under the same conditions plenty of times before.

I've been digging around, turns out advancing the magneto is a pretty common performance trick among the scooter crowd. I'm learning a bunch on this as many scooters use an ignition setup that looks dead on with the 200cc bikes. They will either index the magneto with an offset key or relocate the trigger on the magneto itself (requires welding on the magneto). The Honda XR 200 is similar as well, but a common thing there is to oval out the pickup mounting holes and get some advance that way.
If the 200 really does share igitions with the scooters, that's a good thing. I found two different adjustable CDI modules from Posh that should work.

Looks like 34mm Mikuni flat slide carb, some ignition advance and a good, mandrel bent pipe and free flowing muffler might be the way to go on these bikes.

[fatboy250]

Good investigation work knothead...keep us posted.

[IronFist]

I was thinking of an electronic timing system that runs off points for my CB350. It's a cash thing, because from what I've read they work great. Just too expensive for this season. :oops:

[knothead]

Originally Posted by new2riding

I was thinking of an electronic timing system that runs off points for my CB350. It's a cash thing, because from what I've read they work great. Just too expensive for this season. :oops:

I hate to sound like I'm hung up on lawnmower engines, but...
You can get electronic modules to replace the points on a B+S engine. They pulse the spark and increase it's duration. Last I saw, they were like $12. Since they only replace the points I've wondered id they could be used in other applications. Northern Tools used to carry them and I found them in a small engine shop last year. Might be worth checking into. The points housing on that CB should be big enough to put a couple of the modules inside.

Found one here..linky.

[knothead]

Originally Posted by fatboy250

Good investigation work knothead...keep us posted.

Thanks!
I'll post up some of the better links I have found on getting more power from these engines.. I found a (commercial) site that builds 125cc horizontal Lifan engines to get around 23hp out of them! (I'd be happy with that from my 200!).
I won't be able to do much with my Lifan yet, I have to adjust the valves in the TDM... It's a nice bike, but it's ticking me off, to adjust the valves you have to take the darn thing apart... even down to removing the cams. Between the cost and complexity, it makes Chinese bikes really shine as a good value!
In the meantime I can check the Lifan by putting a dial indicator through the spark plug hole and checking to see if the timing marks line up with the piston at TDC, should be the way to do it.

[truthfriend7]

Hey knothead. Since you seem to be about the fastest one with your bike. Might I ask what other settings/mods you have done? How did you adjust your carby? Thanks

[knothead]

I finally got around to checking the timing mark today. I know you guys have been holding your breath on this one, so here it is.
The timing has been advanced. It's very slight, the mark looks to be around 2mm or so ahead of where it should be with the piston at TDC. Anytime I adjust the valves I check the mark to be sure I'm dead on, so I know the marks should be aligned with the piston all the way up. I wouldn't think that small amount would make such a difference, but that seems to be the case.
I bet there is enough room to modify the pickup mount to gain the same amount of advance... I'll tell you that when I go in to replace the key.

I really tried to get a picture, but I my camera won't focus that close and I don't have enough hands to hold the light, camera and a lens.

[knothead]

Originally Posted by truthfriend7

Hey knothead. Since you seem to be about the fastest one with your bike. Might I ask what other settings/mods you have done? How did you adjust your carby? Thanks

I run slightly rich on the mix, but the bike has had nothing done to it outside of maintenance, I still have the stock airbox even.
I am looking at doing some mods now though. I found 34mm Mikuni roundslide carbs for $89 and the flatslides for $135, a mandrel bent headpipe for $89 and I still have to locate a decent, cheap muffler. I want to get up to 20hp. I think the biggest thing is going to be finding a way to advance the timing and keep it relable.