anyone know about engines?

[Paulwhite]

hello i know its not a bike or a Yamaha but its still an engine and the theory is still the same, cant seem to find anything on the matter so i thought id try here. (id understand if no one replies)

right, iv got a go-kart engine its a honda gx 160 clone (5.5hp) and yes iv looked on google for tuning tips and safe to say iv managed to do most of them!

iv de-governed the engine and put stronger valve spring in so it revs higher (5000rpm), iv put a free flow air filter on and a straight through exhaust, and might be putting a mikuni carb on (a spare xvs dragstar carb with smaller jets )

now iv read up about ignition timing for this engine but i get confused when it comes to figuring out what to do... im wanting to increase the torque cause at the mo when you ride the kart its only hitting about 2500 rpm and dont seem to go any higher. so i thought increased torque = better pulling at low rpm = getting to higher rpm. but do i retard or advance the timing to get this?

you can do this one of 2 ways change the cam gear position (dont want to do that) or get an 8 degree timing wood ruff key.

there is also a aluminum flywheel mod that makes the engine rev faster due to the lighter weight.

what im thinking of doing is make my own flywheel (out of fiberglass and epoxy resign) but make it with the new timing built in, but need to know how to sort the timing out.

cheers for any help (if i get any)

[wild foamy]

would not reccomend building your own flywheel, especially at those sorts of speeds, its likely you will end up wearing it.

my money would be on advancing the ignition timing, but dont quote me on that

[Paulwhite]

well the idea is to make a mould from the original flywheel so assuming that it is perfectly round it should work and be safe, there is a metal cover that goes over it so if the worst happens and it disintegrates then it will just stall the engine. the actual fiberglass will be layered and pressed whilst it sets, so im certain that it wont shatter (only if its not perfectly balanced) but this is where iv red that the original flywheel isnt of a good build quality and have been known to brake apart (ripping through the case). the kart itself is just a homemade toy so wont be doing any considerable speed (probs max 40mph) its just the torque that im trying to increase and with a lighter flywheel it will get to the higher rev range quicker making it pull better.

well you can get a key to advance the timing by 8 degrees but i dont know if that would help the torque? i just want it to pull better but i cant change the gear ratio (not enough room)

but cheers for the imput it was a long shot posting on here but its just a bit of fun

[Airhead]

Stop pissing about with the shite Honda wannabe chinese crap

and see if Cynic still has that old DT125 engine

[2 Wheels]

Paul,

me thinks ya will end up with no honda engine if ya go down this road.

Ya cant get a small engine like that to have alot more torque,,,,,,the piston and bore just isnt wide enough.

[Speedshop]

What you are proposing with the flywheel will be dangerous, ensure you run a cover capable of containing it when it explodes.

If the engine isn't reving past 2500 you've either not set up the cam timing or carburation OR the advance section of the ignition has packed up.

I'm not familiar with that engine, but if its a 2 valve single it won't need a fancy advance curve, but it will benefit from advancing it earlier but keeping the same start point to give good starting.

[Paulwhite]

Stop pissing about with the shite Honda wannabe chinese crap

and see if Cynic still has that old DT125 engine

lol i have thaught about that but iv made it now with the "honda" engine lol still might be interested in that engine though for the sachs as iv just about given up on it.

""Paul,

me thinks ya will end up with no honda engine if ya go down this road.

Ya cant get a small engine like that to have alot more torque,,,,,,the piston and bore just isnt wide enough.""

its a 160cc 4 stroke single cylinder engine and you can increase the torque if you want to throw your wallet at it, but my wallet is full of dust so just going through ideas.

""What you are proposing with the flywheel will be dangerous, ensure you run a cover capable of containing it when it explodes.

If the engine isn't reving past 2500 you've either not set up the cam timing or carburation OR the advance section of the ignition has packed up.

I'm not familiar with that engine, but if its a 2 valve single it won't need a fancy advance curve, but it will benefit from advancing it earlier but keeping the same start point to give good starting.""

the engine should rev up to 5000rpm but when riding it wont go past about 2500-3000rpm cause it only has a 2.5 to one gear ratio, the engine is 5.5hp standard and with the mods iv made, its made it to about 6-7hp, its in nearly new nick and is set up properly,

i hear what your all saying that the fiberglas flywheel is a bad idea.

[Guest gary evans]

hi i would put the honda engine back in the cement mixer it came from and get a two stroke engine in it more power with a power band = more fun and if its not enough for you then tune that up but thats if you can keep it in a straight line,all the top carts are 2 strokes

gary

[choppernorgate]

It can be done, But I dont think the teeth will hold on to it for long,

I would try a smaler cog on the front and a biger one on the rear,

Good Luck

[Paulwhite]

It can be done, But I dont think the teeth will hold on to it for long,

I would try a smaler cog on the front and a biger one on the rear,

Good Luck

yeah iv got a clearance problem with that one. cause its a complete home made bodge job iv got a 44 tooth bmx sprocket on the back and its only just smaller than the wheels so any bigger and itl be running on the sprocket lol and iv had to weld a sproket to the clutch so no hope of swapping that one

i just wanted to get a little more torque, cause it pulls fine on a flat and im 10 stone, its just im not getting top speed out of it and a little more torque would help loads.

but saying that.....iv built it and havent got anywhere to go on it lol (oops) it works so its not too bad, il have to give it a go in the snow and see what its like might even put it up for sale to fund the bike project lol.

[Cynic]

Poor bloody motor will be flogging its bks off. Point of interest, it was go carts that saw the death of many of the DT175's as the engine is perfect for carts, strong torque and decent revs. With no crappy valve gear to drain things.

I have a porly 175 and a porly 125 under the bench, they need rebuilding but you could have a decent motor from the 2, at either 175 or 125.

If you want em let me know.

[Paulwhite]

Poor bloody motor will be flogging its bks off. Point of interest, it was go carts that saw the death of many of the DT175's as the engine is perfect for carts, strong torque and decent revs. With no crappy valve gear to drain things.

I have a porly 175 and a porly 125 under the bench, they need rebuilding but you could have a decent motor from the 2, at either 175 or 125.

If you want em let me know.

oooo dont tempt me lol the go kart is fine... it works ......but i do have a potential project sat outside that needs an engine......its the left over carcus of the sachs roadster.

im definatly interested, do you know whats up with the engines? and what would you want for them? do they come with the other bits and bobs, like carbs, loom, headders ect? pm me m8 then we can have a chat.