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what the heck?!

1722 Views 18 Replies 5 Participants Last post by  darthbeast1983
ok so im messing with my mini quad and i finially got it running. its so painfully weak though, it wont even go through grass.it was a 40MM bore head but i since took the motor out and added a full circle crank and a 44mm bore head. running a dellorto carb and a modded stock pipe with the timing advanced 10 degrees. im thinking its the carb. today i ordered a intake to run a walbro wyk. im thinking the clutch is not helping me at all as well. like its engaging too early. any thoughts?
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crossdrill the clutchpads//blueprint the fitment,, polish the mounting bolt holes/screw shoulders and add hp springs..

When you added the bbk did you blueprint the fitment and did you clean up the porting on the kit...Those BBK's have to be improved to be of any real power........
u got any pics cam2?
Hate to ask but are you sure when you put the rocket key in that you put the step towards the exhaust?
Hate to ask but are you sure when you put the rocket key in that you put the step towards the exhaust?
im positive i put the key in right, i had the identical engine on my cag and it wheelied due to the shear power! has me stumped, i did pull it apart to install a full circle crank though so ill take it apart tomorrow.
What about your head gasket, sometimes on a seperate head when you torque it down it don't seat right and it leaks.
i took it apart and everything was dead on. i think its the cheap dellorto clone. and the old age. actually alot of things. i need to rebuild it badly. i was goofing around in the mud and it got alot hotter then what i would of liked and died, im pretty sure i cooked the piston and rings. and probably the wrist pin bearing. i mean the engine was smoking! and not out the exhaust. i let it cool down and when i shot some WD-40 in the carb it started and ran like nothing ever happened. i think the carb and clutch combo is drowning the gains of the modded pipe. the clutch is seriously working against me. if i had a good stocker id "cam2" it but i know its done. she slips on dry pavement. im not a big fan of lightened flywheels because of less cooling but im considering it....
Maybe the clutches are grabbing, on my C1 I blew a pad off one of the shoes and it got the engine very hot and smoke was pouring out of the clutch housing cooling slots.
i took it apart and everything was dead on. i think its the cheap dellorto clone. and the old age. actually alot of things. i need to rebuild it badly. i was goofing around in the mud and it got alot hotter then what i would of liked and died, im pretty sure i cooked the piston and rings. and probably the wrist pin bearing. i mean the engine was smoking! and not out the exhaust. i let it cool down and when i shot some WD-40 in the carb it started and ran like nothing ever happened. i think the carb and clutch combo is drowning the gains of the modded pipe. the clutch is seriously working against me. if i had a good stocker id "cam2" it but i know its done. she slips on dry pavement. im not a big fan of lightened flywheels because of less cooling but im considering it....
I only lighten my flywheels on most of my cags to 12 fins for my wickedly modded engines that run a tight squish which makes engines run hot but cooling isnt too affected when you add an all aluminum pullstarter that becomes a heatsink to draw heat away....Another thing that makes them run hot is airleaks,,weak anemic fuel flow,,improperly jetted carb.....

Check the rings in the piston to see if theyre loose....

How did the copper ring look when you seperated the headcap?...Any black marks from compression loss?

When you reassemble it do a squish test and compression test on it...
I only lighten my flywheels on most of my cags to 12 fins for my wickedly modded engines that run a tight squish which makes engines run hot but cooling isnt too affected when you add an all aluminum pullstarter that becomes a heatsink to draw heat away....Another thing that makes them run hot is airleaks,,weak anemic fuel flow,,improperly jetted carb.....

Check the rings in the piston to see if theyre loose....

How did the copper ring look when you seperated the headcap?...Any black marks from compression loss?

When you reassemble it do a squish test and compression test on it...
im running a stock head. i think my carb is shot. cant wait till my manifold gets here. i havent pulled it apart yet. i was too tired from painting my camaro. im actually amazed it started back up!
im running a stock head. i think my carb is shot. cant wait till my manifold gets here. i havent pulled it apart yet. i was too tired from painting my camaro. im actually amazed it started back up!

It would after cooling...Ive overheated many r/c nitro engines over and over and they kept running after cooling down..........
riddle me this, is it normal to get any endplay on the crank(in and out movement)
riddle me this, is it normal to get any endplay on the crank(in and out movement)
Yes but theres a tolerable amount..Too much and youll get harsh harmonic distortion at high revs........I use anerobic sealer to set the bearings in the case so theres .009" of side play on both sides of the crank...
ok so i brought the quad home and tore the engine down, got my WYK carb intake and made some grim discoveries. first and formost the head gasket has been compromised. also the intake gaskets were done too. just a big oily mess, wondering on how in the heck this thing didnt ignite lol. piston and rings are gouged. so im thinking of doing a CAM2 twin carb but with a 1 piece ported head...
I had the same problem with my gaskets this summer, so i replaced some of them, and used a layer of Yamabond for head gasket. once blueprinted, honed and reworked the 1 pc 3 port head works great and delivers great torque throughout the power band. Havent tried a twin carb setup before, but a real walbro wt603 pumper with proper tuning does quite well on its own.. Im running a 44mm 1 pc 3 port head with windowed piston on my quad right now, cf reeds, fc crank with upgraded bearings and moded stock pipe, a authentic walbro wt603, ultralight flywheel that I balanced, rocket key, K&N style filter, moded aluminum clutch arms with HP springs. I polished the inside of the crank case aswell to make it smooth as a baby's ***.

This setup delivers alot of torque, had alot of fun with it in the snow. I have yet to try it in a regular pocket bike frame, Im sure its hella fast.
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i honestly dont think im doing a twin carb on my quad. im looking at a nice 3 port 2 piece head for it, it pains me that its in the shape its in because its suppost to snow for 4 days and i wanna play some mountian madness =( i got a nuked piston with clutches to match....
i honestly dont think im doing a twin carb on my quad. im looking at a nice 3 port 2 piece head for it, it pains me that its in the shape its in because its suppost to snow for 4 days and i wanna play some mountian madness =( i got a nuked piston with clutches to match....
I just ordered a whole bunch of parts Im gonna be trying the 44mm 2 pc 3 port head. I'll let you know how it stacks up against the 1 pce head with similar mods done. I REALLY like the 1 pc 3 port though, there is absolutely nothing wrong with it.

-25 celcius out where I am. too cold to ride. :(.
cover-alls and groves man....
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