Free tips for mini dirt?
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condog
Member
1. Make your own free flow filter. Make sure you use the cage of the old filter too keep back pressure.
2. Find a bigger kehin or mikini carbie like a 22mm, 24mm or 26mm of any old japanese mini bike. Most the china 110cc and 125 cc have 16mm standard. At tops the carbie might cost you $15 from a wrecker and would be worth every cent.
3 If you know what your doin you can weld or machine the head and or change the head gasket to change the compression ratio.
4. You could run two2cool in your oil which would cost about $3 per change and lowers engine temps which will improve Hp after the engines hot.
5. You can play with the clutch spring / washers depending on manufacturer and make it hit later so that the engine always operates closer to peak hp. Harder springs / washer setups = later hit and thue faster more aggressive auto clutch response. But be warned this mod menas your gearbox and drive / engine parts will last way less time. If your this serious you really should just buy a thumpster as most the above are done.
2. Find a bigger kehin or mikini carbie like a 22mm, 24mm or 26mm of any old japanese mini bike. Most the china 110cc and 125 cc have 16mm standard. At tops the carbie might cost you $15 from a wrecker and would be worth every cent.
3 If you know what your doin you can weld or machine the head and or change the head gasket to change the compression ratio.
4. You could run two2cool in your oil which would cost about $3 per change and lowers engine temps which will improve Hp after the engines hot.
5. You can play with the clutch spring / washers depending on manufacturer and make it hit later so that the engine always operates closer to peak hp. Harder springs / washer setups = later hit and thue faster more aggressive auto clutch response. But be warned this mod menas your gearbox and drive / engine parts will last way less time. If your this serious you really should just buy a thumpster as most the above are done.
condog
Member
Modiify carb and filter so you have a forward facing carb
Also have a look at this
http://dratv.com/dratv/125ccenginekit.html
This site has all sorts of good stuff for Honda engines and includes heaps of free or low cost mods and ideas.
Also have a look at this
http://dratv.com/dratv/125ccenginekit.html
This site has all sorts of good stuff for Honda engines and includes heaps of free or low cost mods and ideas.
condog
Member
read the post above genius it was a tack on.
Also take a look at the pros all changed to forward facing carbs, acts like a sump pressure fuel pump.
Why dont you see if you can contribute Einstein.
Also take a look at the pros all changed to forward facing carbs, acts like a sump pressure fuel pump.
Why dont you see if you can contribute Einstein.
condog
Member
Its the same principle behind bonnet scoops on high performance cars and turbos.
In simple terms if you provide intake pressure of air and fuel you get a bigger combustion explosion and higher power output from the engine.
By facing the Carb and air filter forward the movement of the bike will act like a very mini turb, particularly at speed. And hence the reason why a foam uni filter is better then the convoluted paper and mesh filter which have a solid end. The solid end would block the best area for intake pressure.
It may at best add about 1 hp at top med to high speed, although i have not read of any measurements.
When your dealing with 70-90kg pilots , 60-70kg bikes and engines with only 8+ hp then every little bit helps.
In simple terms if you provide intake pressure of air and fuel you get a bigger combustion explosion and higher power output from the engine.
By facing the Carb and air filter forward the movement of the bike will act like a very mini turb, particularly at speed. And hence the reason why a foam uni filter is better then the convoluted paper and mesh filter which have a solid end. The solid end would block the best area for intake pressure.
It may at best add about 1 hp at top med to high speed, although i have not read of any measurements.
When your dealing with 70-90kg pilots , 60-70kg bikes and engines with only 8+ hp then every little bit helps.
ah yeah i get ya, sorta like ram flow on a road bike, im not having a got at ya but personally i dont see it helping at all on a mini bike especially one of the cheap 110 minis, by the amount of dirt that i get in my face from the front wheel i would say the air cleaner would cop it sweet.
maybe if you did alot of flat track or super motard with high speeds it might be a good idea.
maybe if you did alot of flat track or super motard with high speeds it might be a good idea.
condog
Member
In mud its probably better to have backward. When youve got such under powered bikes everything helps. The bloke wanted free mods so thats one for him that will have some performance beneift. Not a huge amout, but what do you get fo free.
condog
Member
Dont go for too much extra air unless you have a richer main jet, or you will be too lean. They only cost about $3 but its just a matter of having a few.
condog
Member
Check this out carefully cause the newer engine tuners do it different to the way it used to be done. You definitely want a big carbie and air intake (filter) but most modern port jobs dont enlarge the manifold they fill it and shape it with epoxy. The smaller manifold pulls unrestricted air and fuel from a larger carbie at high speed thus creating a better vapour mixture for higher quality combustion.
I founda picture link somewhere on Thumpertalk if you do a search for epoxy port job you may find it.
I founda picture link somewhere on Thumpertalk if you do a search for epoxy port job you may find it.
There is no way just turning your carb and facing it forward is going to make any difference. Even when using a foam type filter the air flow is going to deflect around the filter. Yes, I know some riders are doing it but that dosent mean that it works. A number of road bikes are using "ramair" type systems to increase power but have a good look at them. The air flow is fed by ducts into a sealed airbox and at high speed (most engineers say 200kmh +) a small positive air pressure is achieved. When this is conbined with a properly set up carb or efi system a small power increase is possible. Note the the speed required is far greater than any mini dirt bike is going to achieve, and I think it may be a bit difficult to fit the sealed airbox & the ducting! :lol:
I agree with the advice about using a bigger carb, and have a look at the intake to make sure that there is no steps to interupt the air flow. Ideally you want a slight taper leading from the carb to the intake port. One bike I worked on this week had a 24mm carb and intake but had an insulator between them with an 18mm bore. Just enlarging and cleaning this area made a big improvment to top end power. If your original pipe is overly restricted an aftermarket pipe will help but may not be worth the expence. You can open up your pipe to remove some (but not all) of the restriction. Use a unifilter, not so much for power but for the improvment in filtering compared to a paper one.
Sorry to discredit your post condog, but with 27 years of experence race preparing bikes I feel my points are valid.
I agree with the advice about using a bigger carb, and have a look at the intake to make sure that there is no steps to interupt the air flow. Ideally you want a slight taper leading from the carb to the intake port. One bike I worked on this week had a 24mm carb and intake but had an insulator between them with an 18mm bore. Just enlarging and cleaning this area made a big improvment to top end power. If your original pipe is overly restricted an aftermarket pipe will help but may not be worth the expence. You can open up your pipe to remove some (but not all) of the restriction. Use a unifilter, not so much for power but for the improvment in filtering compared to a paper one.
Sorry to discredit your post condog, but with 27 years of experence race preparing bikes I feel my points are valid.
crazzy #1
Well-Known Member
i dont thnk it would do much
beau tucker
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ay lads new 2 the game my xr 50 is in peices was wondering what i can n cant put on it 2 race the 88c limited class eg.forks wheel size& best products
FOXraceWES
Well-Known Member
Which is better? (Carby)
That is the Carby on my bike I am getting. Just wondering, would it be better to put a mesh metal one on?
That is the Carby on my bike I am getting. Just wondering, would it be better to put a mesh metal one on?
