New 79cc build

birdmannn101 · Dec 16, 2013

SB, That is what I am using, the "max torque clutch" with a jackshaft instead of the Q matic transmission. So, I have 2 chains to deal with while you have 1 chain and 1 belt. One of the 2 chains always gets some slack in them. Heck, that might be what is causing the clutch chatter and vibrations.

runnermike · Dec 17, 2013

Which chain is it...from the clutch to the input, or your chain to the rear sprocket? It could possibly be alignment if the chain is tight and then goes slack.

culvercityclassic · Dec 17, 2013

It's the clutch that causes the chatter... Spend the money one time and purchase the right clutch. End of debate.... Now back to the orig post....

runnermike · Dec 17, 2013

lol........

headtrama · Dec 17, 2013

birdmannn101 said:
The only problems I have areth what I found on the Internet. It says 3/4" bore drive with 3/16" keyway and my HF79cc is 5/8" drive.

Factory Set to engage at 4000 RPM. The HF79cc engine Maximum speed (rpm) is 3600 RPM with a Maximum Torque (ft. - lbs.) 3.5 ft. lbs. @ 2500 RPM, so I'm thinking this might not work in my case.

This racing clutch looks like what I need if it fit the engine.

With the Governor removed that motor should go to 5000 rpm easy

PAracer · Jan 10, 2014

Headtrama, what's the 411 on the upgraded valve springs? Where did you find them? Are they predator 212 or handa parts? I am very interested in getting a set.

Thanks!

headtrama · Jan 10, 2014

These are the springs i have been running and the place i get them from
http://www.doverpoweronlinestore.com/catalog/item/8251221/8954788.htm

headtrama · Jan 10, 2014

I swapped out my 79cc for a 99 cc today , What a difference some cc's make . The bike is actually fun to ride now .

Im going to have to soften the clutch now because it hits a little hard on take off . Only thing done to the motor is I decked the head for more compression and cleaned up the ports and heavy valve springs .

When I was fitting the stainless steel clutch shim I made for the cheetah clutch I slashed my hand open on it and had to get stitches today . So I didn't get much time to ride it . But it rode well on its first ride .

PAracer · Jan 10, 2014

Sorry about the injury. Ive mashed and slashed myself pretty good a few times over the years. Not fun.
Ive read that you can use the 79cc head gasket on a 99cc block. The 79cc gasket is .030" thinner.
Thanks for the note about the springs. Sounds like a set of upgraded clone springs would work for me.

buba · Jan 11, 2014

head --sorry to hear it took its' toll in blood--heal quick

best

silverbear · Jan 11, 2014

headtrama said:
These are the springs i have been running and the place i get them from
http://www.doverpoweronlinestore.com/catalog/item/8251221/8954788.htm

Is there a guide somewhere on how to swap out the springs? I was thinking about picking up another 99 Predator. Are they still available anywhere?
SB

headtrama · Jan 11, 2014

The springs are a easy swap, affordable go kart has a build up of a 99cc motor on there website. The 99cc is no longer available.

F_Rod81 · Jan 11, 2014

headtrama said:
I swapped out my 79cc for a 99 cc today , What a difference some cc's make . The bike is actually fun to ride now .

Those extra 20cc's do make a big difference. I recently swapped the stock springs in my 99cc for the 18lb springs from AGK, wow no floating at all. (^)

F_Rod81 · Jan 11, 2014

silverbear said:
Is there a guide somewhere on how to swap out the springs? I was thinking about picking up another 99 Predator. Are they still available anywhere?
SB

SB,

Here is a video describing one way to perform it...

clone valve spring swap/ set

gokart25 · Jan 11, 2014

F_Rod81 said:
Those extra 20cc's do make a big difference. I recently swapped the stock springs in my 99cc for the 18lb springs from AGK, wow no floating at all.

what do you mean floating? what does the motor sound/act like when floating?(chuggs or cuts in and out?)

maniac57 · Jan 11, 2014

I've always found my bikes run better after being christened with blood, sweat and tears.
I have also been known to dance naked at midnight on a full moon at the local dirt track....
smeared with 90 weight gear oil and wearing cheap sunglasses.

scotto- · Jan 12, 2014

maniac57 said:
I've always found my bikes run better after being christened with blood, sweat and tears.
I have also been known to dance naked at midnight on a full moon at the local dirt track....
smeared with 90 weight gear oil and wearing cheap sunglasses.

In the winter? laff

What do the neighbors think?

headtrama · Jan 12, 2014

I got some more seat time on the bike today . I rode over to culver city classics today and the bike ran really well . The motor will rev past 6000 rpm but I like to keep it about 5000 5500 rpm .I let Jeff ride it and he seemed to like the way it rode . Thanks Jeff for hooking me up with the 99 this bike is way more fun to ride now .

culvercityclassic · Jan 12, 2014

Ya the bike runs great Andy... Made me work on mine after you left.... Ha ha

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New 79cc build

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