I'm going back and forth about a lot of things on this build-up. What do you guys think?
Stuff I have to work with
GX160 Jiangdong clone.
GX200 Genuine Honda.
What would you build as an example of a "mild" alcohol motor? I want to use the fuel, but not for high revving shenanigans. This is more of a study in torque. The challenge is to make ample torque off of idle, opposite of high rpm usage. The bike does 40mph already, but has a little trouble off the line getting there. A TAV is about the only modification I would consider to increase top speed. This thing at 75mph would be a death trap and already is getting a GS425 front brake.
The Good Doctor runs very well with very little modifications to the motor. I wanted a small showcase of alternative fuels that wouldn't kill me or interested folks that want a ride. I also wanted it to be easy to maintain.
I'm mostly happy with the bike's performance with just an open element filter and a header. A rejet and timing bump is all I have planned for basic, cheap mods.
The bike runs great even geared down to 5:1. I'm purposely limiting the top speed. What's funny about this is the amount of torque available. I've done practically nothing to the motor and it almost seems too fast already. If it needs any help it's just off idle with that numerically high gearing.
Thoughts? I think there's plenty to be had with just a timing bump. I think a high compression, low rpm build might be "too much." I don't want the bike to walk off and leave at idle like it does on nitro mixes and an open choke. I want a motor dialed in before stripping the chassis for paint.
-Should I consider a GX160 carb on a GX200 for torque?
-Would just a GX160 head on a GX200 be plenty to raise compression? Maybe keep the smaller carb?
-Would just a timing bump, GX140 emulsion tube, and rejet be all that's needed for better low end on -5:1 gearing? On cam it's fine, but off cam it's a bit of a dog at 5400ft. elevation.
-How would you make a lot of torque below the 3600rpm stock rev limiter for cheap?
Stuff I have to work with
GX160 Jiangdong clone.
GX200 Genuine Honda.
What would you build as an example of a "mild" alcohol motor? I want to use the fuel, but not for high revving shenanigans. This is more of a study in torque. The challenge is to make ample torque off of idle, opposite of high rpm usage. The bike does 40mph already, but has a little trouble off the line getting there. A TAV is about the only modification I would consider to increase top speed. This thing at 75mph would be a death trap and already is getting a GS425 front brake.
The Good Doctor runs very well with very little modifications to the motor. I wanted a small showcase of alternative fuels that wouldn't kill me or interested folks that want a ride. I also wanted it to be easy to maintain.
I'm mostly happy with the bike's performance with just an open element filter and a header. A rejet and timing bump is all I have planned for basic, cheap mods.
The bike runs great even geared down to 5:1. I'm purposely limiting the top speed. What's funny about this is the amount of torque available. I've done practically nothing to the motor and it almost seems too fast already. If it needs any help it's just off idle with that numerically high gearing.
Thoughts? I think there's plenty to be had with just a timing bump. I think a high compression, low rpm build might be "too much." I don't want the bike to walk off and leave at idle like it does on nitro mixes and an open choke. I want a motor dialed in before stripping the chassis for paint.
-Should I consider a GX160 carb on a GX200 for torque?
-Would just a GX160 head on a GX200 be plenty to raise compression? Maybe keep the smaller carb?
-Would just a timing bump, GX140 emulsion tube, and rejet be all that's needed for better low end on -5:1 gearing? On cam it's fine, but off cam it's a bit of a dog at 5400ft. elevation.
-How would you make a lot of torque below the 3600rpm stock rev limiter for cheap?
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