50cc 50mph+ secrets?

I know all guys that know a thing or two about tuning hate to give real advice about serious issues to anyone but your homies, but I just thought I would ask some questions. Here's what I got: Pinto e50 matched to a 50cc tccd, 16mm phbg, bullet pipe, ported the crap out of the exhaust and widened and lowered the intake about 1mm, (my exhaust duration is about 200 degrees), I am jetted proper, 15-45 gearing.. Umm I think thats it.. The highest I saw on gps was 41.77 with this setup.. I read the graham bell book cover to cover, and I am just wanting to squeeze as much performance out of this 50cc kit before switching to something larger. I weigh 220, so its a dog off the line, but its got good pull after about 10mph. I am thinking it probably needs a new pipe to get it over 50 for sure, but thats still 8mph away. I don't see a pipe giving that much on a 50cc, unless those bullet pipes just really stink. Was thinking about cutting my piston skirt to increase my intake open duration, but I wonder how much to cut. Thanks for all the info, I've learned a lot just reading books and your posts, so I'm not a beginner, but Im not a guru either, just want to take it to the next level. Thanks.. Oops for the lengthy post

1236479868_pinto.jpg

Re: 50cc 50mph+ secrets?

time for gearing and clutch adjustment, 16 front?

Re: 50cc 50mph+ secrets?

Re: 50cc 50mph+ secrets?

Im no guru either.

I just widen/port/etc try it, if its needing more, widen more, etc.

Try and get your compression ratio to 15:1

Get another pipe, bullets are not that " performance "

I had and others have 6p's on 50cc

Gear up to 16t or 17t as well, but if you think your low end sucks now, just wait till you get it up to a 17t

Re: 50cc 50mph+ secrets?

i'm running 18x36

Re: 50cc 50mph+ secrets?

Lowering the intake was the same as cutting the piston skirt but you could go 2 more mm on that but it may slow your low end more. With 50cc you are always dealing with a low/high end balance and that you weigh exacerbates that dilemna. I checked the performance of a bullet and a Homoet 6p back to back on a hot 50 and the 6p was only good for about 2 mph more. If you were to do a compression test what would it come to? You could shorten the Bullet at the header and or the dwell section of the pipe for higher pipe RPM action. The header on these pipes extend 2 and a quarter inches into the expansion chamber. The 6p is about 2 1/2 inches shorter than the Bullet. An auxilliary center bleed welded onto the Bullet will help. Use maybe 45 psi or more if you have good tires to compensate for your weight.

Re: 50cc 50mph+ secrets?

) Cupermcnewbster ( /

whats up with your ignition? My friend ran about 43-45 with his tccd and a 12 bing. It took forever to get there, but it did eventually.

Re: 50cc 50mph+ secrets?

! http://www.brandchannel.com/images/FeaturesProfile/profile_img1_slimfast.jpg1

Ok, in all seriousness, you need your kit to rev higher. A great way to do that is by increasing the transfer window duration. The ideal way to do that is by raising the entire cylinder up by placing a metal gasket like shim between the case and the cylinder of the height you need the transfer to be increased by and shaving off the same amount from the top of the cylinder, thus keeping the same displacement but having much more aggressive timings.

Your problem is that you already have the exhaust duration maxed out and there is nothing to reverse that, save a new cylinder. It is not the best idea to hack away at the transfer windows, they _should_ be angled in such a way as to best promote cylinder scavenging and modifying them would not be beneficial to overall performance.

So:

Cut weight and re-gear!

Re: 50cc 50mph+ secrets?

GHAAAAAA

fail :(

Re: 50cc 50mph+ secrets?

My stator is all the way left. Full advance. Points are clean. A few days ago I put an 18t on the front and tested it. I noticed that it wouldn't wind up as high as with the 15t front, so it reached about the same speed. 41.37mph actually. And it was even more of a dog off the line. I know that a cdi would advance my timing more, and help with allowing proper ignition at high rpms, but I don't really have the money. Thanks for the great responses by the way, that is some helpful info. I think that my rpms are being restricted a lot by the pipe I have. Maybe if I got a better midrange pipe, that would let me regear and have enough power to pull to the higher rpms, but as is, it hits a wall. I have yet to check compression, but I will. What psi am I looking for?

Re: 50cc 50mph+ secrets?

Steve has it down, his hot 50 was quick all around with a 6p.

Look for 210 psi on compression

Re: 50cc 50mph+ secrets?

CDI will not help you much.

It is logical that with higher gearing, you won't reach the same RPMs. With higher gearing, it's harder for the engine to spin up high. If you want super high RPMs, gear low. You won't go very fast, but you'll accelerate quickly, and really whine up there, because the engine has to turn more RPMs to get the same speed.

Blah, I'm drunk. Experiment with your timing more than simply running it at full advance. Timing is really a touchy beast, and the power is really in the points. Honestly, correct timing changes EVERYTHING. But yeah, you should be running at least 16x45, if not 17x45. The 50cc TCCD is notorious for shitty low end. You need to tune your clutch to at least TRY to compensate.

Bullet pipe is not ideal.

Re: 50cc 50mph+ secrets?

Im gettin low 40s on my e50 stock cylinder #11 with derestricted stock exhaust, 15 bing 17x41 gearing, I weigh about 140.

Re: 50cc 50mph+ secrets?

I have this kit with 16X45 gears and it gets about 45 with a 14 bing and a boss. I would definitely try the 16 tooth front if I were you. It still revs up nice and I doubt the low end would be that much worse.

You will definitely have to do some major clutch work too. Right now I have a two shoe with PAZ springs tightened as far as they will go. Even with this it still doesn't seem like the motor has enough power to rev up before the clutch grabs. I would recommend getting a three shoe with paz springs or lightening the two shoe.

This kit really is solid once you figure out the low end. Tons of fun in the midrange and revs to the moon. Seems like with a 16 phgb and all that porting you should be going faster but what do I know.

Re: 50cc 50mph+ secrets?

) CuperAWESOMO ( /

There is power to be gained in a lot of places. open up the transfers at all? Try doing some pipe tuning? Guru was telling me about how 50cc bikes are far more sensitive to the pipe dimensions. Also told me about his top secret (well not really) tapered header technology that helps a 50cc tremendously.

Re: 50cc 50mph+ secrets?

Sealed wheel bearings, chain tension, tire pressure, proper timing, 18x40, clutch tune, brake drag, air leaks and girl pants.

Re: 50cc 50mph+ secrets?

Rafter.... SHHHHHHHHH

Re: 50cc 50mph+ secrets?

girl pants.

Re: 50cc 50mph+ secrets?

Ϫ‡☄ಬ∞ ƀƖḬƝƊ ƤǂƿƎ ∞ಬ☄‡Ϫ - Hoke from Black Pipes Moped Gang /

girl pants

Re: 50cc 50mph+ secrets?

ies

Re: 50cc 50mph+ secrets?

Thaddeus Koscuisko /

Tapered Pants ...

Re: 50cc 50mph+ secrets?

girl drag

Re: 50cc 50mph+ secrets?

i hit 45.4 gps on my 78 n with a stock magnum jug and a 19phbg and 6p 18*50 and lots of clutch work i think it would have hit 50 will one of you small fuckers i am 300 lbs so fuck it that close to 50 for me to say i do 50 on 50cc

it is all in the 210 psi on compression

Re: 50cc 50mph+ secrets?

Bryan, but you didn't hit 50mph, so don't be fooling yourself and go for a jog and lay off the fast food.

Re: 50cc 50mph+ secrets?

Fuck health. What could be more motivating than to lose weight for the cause of speed.

Re: 50cc 50mph+ secrets?

if you have your stator maxed out on advance you need to set your point gap wider, that will have the same effect. on my 47 mph pinto i was running as big of a gap as i could without the points not closing at all, and the stator plate was about in the middle.

also, tiny pipes. a shortened header proma GP would probably be about perfect for a 50cc blaster, or a shortened techno BOSS. but yea, on the top end, bullet is going to be about as good as anything. when you really start scrappin' thats where the extra 1-2 mph come from. I had my plug side-gapped, my 16mm bing was bored with a taper, just about everything possible to grab an extra .1 mph here or there.

fat tires dont help either, the smaller and balder the tires, the less resistance.

mags are going to hurt you quite a bit from the extra drag on the 'spokes'

Re: 50cc 50mph+ secrets?

Ican easilyreach50 on myped, but it helps to have the tires inflated andonly weigh 120.. loseten pounds and you will get there

Re: 50cc 50mph+ secrets?

Nick, learn to use the space bar.

Re: 50cc 50mph+ secrets?

Ya im sorry about that. i was using the computer in a library and the keyboard was driving me nuts...

Re: 50cc 50mph+ secrets?

My gap is .018 right now.. Maybe .020? I'll try it!

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