performance cam By scoot (Read 1,368 times)

[scoot]

Can any one recommend a good street cam,for a 150 cc scooter I don't race the scooter but would like a little more performance without damaging the reliable of the scooter any help would be welcome.

[Bashan]

I used an A12 on a BBK and it worked great. The lobes are pretty aggressive and it wasn't easy to turn over. I think I'd go with a high torque starter. I also had a small issue with the exhaust rocker hitting the valve cover. That could have been because of the new valve apparatus or the cam AND valves. But all I did was file the inside of the cover down a little and it stopped.

[scoot]

scoot,Bashan Hi do you know anyone that makes a valve cover that is higher than stock? I have no problem relieving the stock value cove but it would be much easier if this part is already available.also will the stock cam chain work with this cam.and if not will I have to split the cases to install a new cam chain.and that brings up another ? do you have to split the cases to replace the cam chain I'm new to gy6 mechanics so if I sound stupid please forgive me I've read that if you drop the cam chain when you are replacing the head gasket, your really in trouble, I've replaced the head gasket on my scooter and was very careful not to lose the chain to the bottom of the motor.back to the cam you said you used this cam on a bbk I assume that is a big bore kit do you think this cam is compatible with a stock motor? I may go to a big bore kit in the future but not so soon I'm now running a dr.pulley variator with 10gm.sliders 1500 rpm torque spring and 1500 rpm clutch springs also I've upgraded the cdi and coil. The high torque starter sounds like a good up grade even if I never go to a big bore kit. (LoL)I'm going to a big bore kit just a matter of time .so is this cam a good fit or I'm I over camming a stock motor. thanks for your help. you sound like you really know what your talking about and one gear head to another thats what i'm looking for. Thanks again.

[Bashan]

I used a new but stock cam chain. I guess the tensioner took care of any differences if any were actually present. I dropped my chain down in the tunnel countless times. Make yourself a wire with a hook on the end and you can fish it out of there pretty easily and even get it on the right drive gear. So don't get all paranoid about that like people like to do, it's not a big deal. You don't sound stupid, don't worry about that. We've all been on that side of the GY6 wrench at one time and don't let anybody ever act like they haven't, because they have. Yes, that cam should be compatible with a stock motor, the only thing that changes are the lobes. I don't think you'd be over camming but let me ask Cyborg before you order one. The timing and everything else is the same. I would try your stock valve cover and see if it hits, it may not, not all of them do, in fact most don't. I think you have to split the case to change the cam chain but I would just stick with the old and save yourself splitting the case. But if you do it's really not that big of a deal. Have you read GY6 Project? It may help you as a guideline. I'll send a PM to Cyborg and ask him about the cam being too big. Here is an A12 vs a stock cam:

If you have more questions we are here. Rich

[scoot]

Hey thanks I'll wait to see if cyborg chimes in before i order. just looking at the cam in the picture it looks like it has a lot more deration and more lift.so if scooter motors are like car motor that means the values are open highter and longer and that makes more H.P. and makes me happy.thanks again you rock.

[cyborg]

You hit it on the head ,,, not a crazy amount of more lift but longer duration ,,, and if you look you'll see it's a modern thought grind,, the lobe is asymmetrically ground,,, it does look like the cam billet is indexed on the gear more advanced than the stocker,,, I would think it will increase bottom and midrange numbers nicely

[Bashan]

FYI folks, Cyborg had his own cams, among other components, made for OSTTITDF builds including a Harley and many Ducatis. Huh? Oh...OSTTITDF means "oh sh!t this thing is too damn fast", that's what you say when you hit the go handle. He knows from whence he speaks.

[Bashan]

Here are the observations Pete (Cyborg) sent me based on the two pictures that I posted above:

1. Also as a side note I also noticed the drive gear is also of higher quality ,, the "teeth" are formed more uniformly and have a better tooth root angle and also that means a better pitch diameter for a more consistent chain tension ,,, boil it all down it means this cam will run smoother and will hold time better,,,,the original is just a stamped POS with no machining ,,, the a12 cam is constructed much better,,,, that's all I can get out of the pic,,, I'd have to have it in my hands to say any more,,,, so buy it alright already

2. we just scratched the surface on valve train geometry ,, we can start correcting valve angles , spring seat pressures , spring surge, etc.

3. the a12 cam is advanced a few degrees and the lobe thats showing has a broader nose so it's a longer duration open ,,, looks like no significant lift difference,, it's a modern grind tho because the cam lobe is ground asymmetrically ,,, probably give good low to midrange power

4. these are non-interference motors, therefore the cam could be installed completely out of time but would not harm the piston or valves, they simply cannot touch.

[scoot]

Bashan Hi again, do you know who makes the cam in the pictures I looked on the internet and lots of suppliers carry the a12 cam ,after hearing all that Pete had to say I want to be sure I'm getting a quality part. or are all performance cams coming from the same manufacturer so it doesn't really matter what suppliers you buy from.I know a cam isn't a really big ticket item to buy, but the time it takes to install one is not something you want to do again 6 months down the line because the cam you end up with was a p.o.s. Thanks again. Bashan cyborg

[cyborg]

No problemo,,,

[Bashan]

Click on Unique Scooter Parts at the top of the site. Contact name is Walter. I bought my cam and BBK from him. I didn't see the cam on his site but just tell him Rich from Scooter Doc said to contact him and tell him you want the same A 12 he sold me. If he can't get it he'll tell you where to get it. Walter is a very nice and helpful man, he will help you out. Rich

[scoot]

Bashan THANKS, I have dealt with Walter already I purchased a DR. PULLEY variator and other parts from him and have been very pleased. And your right, he is A good guy, answered all my ?'S and shipped the part a.s.a.p. in fact unique scooter parts was the first place I looked for the a12 cam ( Walter if you read this don't get a big head and make me a liar)so after all this conversation back and forth I now know what cam to use and where to get it and that is what makes this site so useful, good work guys hope you keep it up .because there is a lot of people out there like me that just don't know.but want to know , and want to know the right way.Thanks again (do I go on and on to long)don't answer that ha,ha.later

[Bashan]

No man, you can keep going on and on as long as you like. That was all headed in a real nice direction. I don't mean for me of course, it's just Pete has this fragile ego and needs his props. Fragile ego......

[scoot]

Well, if that's what it takes to get the right info to the right people than we'll boost BOTH of your ego's as much as you can stand. (just don't let it go to your heads, You both rock) and my hat is off to both of you to take the time and effort to help all of us. Thanks P.s. I don't mean to diminish the contribution of other members I think we all contribute to this site in one way or another by asking ?'s and giving answers we all benefit.One last thing alway remember ride shiny side up rubber side down.Later scoot,Bashan,cyborg

[cyborg]

WHAT DID I DO NOW!!!