so cant seem to find a retailer with billet heads in stock

[desolation]

looks like the only option for heads is the punch head. which doesn't seem to be to bad, every retailer i check for mm heads is out :/. but which punch head do i use with 8mm studs and do i have to use 2 head gaskets when mounting ?

 

[CroMagnum]

Did you check eBay? Link

Made by a member here - Link to thread


Note: I have no connection to crmachineman and don't even know if these heads are any good. Just passing along the info. Of course, if crmachineman wants to give me one for free, I'd be happy to evaluate it.

 

[haddenboy]

I think you meant Puch head, and you can find them at treatland. Its a site specially for moped parts, google it.

 

[Hoze513]

CRmachineman sell some beautiful heads and he has a lot of details on them. He sell on ebay too.

 

[crmachineman]

looks like the only option for heads is the punch head. which doesn't seem to be to bad, every retailer i check for mm heads is out :/. but which punch head do i use with 8mm studs and do i have to use 2 head gaskets when mounting ?

Hey dude!
You still have a billet head option! Not only are they available through my ebay store, but already three other vendors are getting ready to carry these heads, and I expect more vendors will start carrying these heads in future.
The puch head wasn't designed for this motor; the cooling fins are not oriented to allow smooth air flow when used with the grubee engines. If you have to stack head gaskets, then the squish band is lost. The combustion chamber of the CR Machine cylinder heads has been precisely designed for the Grubee 66cc engine with 8MM studs.
There are some problems to overcome if you have a GT-5 motor. If you do, I have complete kits to deal with that problem.

Here is the link to my ebay store:

http://www.ebay.com/itm/Motorized-b...ies&vxp=mtr&hash=item1e6f5e313d#ht_1445wt_906

If you have any questions about this, I'd be happy to try to help!
Thanks,
-Fred

 

[Harold_B]

So Fred, you mention that you've set aside the 49cc head. Is that a dead project? In MI 50cc is the max engine size for a moped so I can't take advantage of all of the neat 66cc stuff (please play violins here). I did snag a Puch head off eBay and I'm in the process of cleaning it up and modifying it but a purpose built head would suit me better. Just for curiosity sake I brought home an IR camera from work so that I can benchmark the temperatures of different heads. This is the "stock" head after warm up and then running again on a stand.

 

[crmachineman]

Hi Harold.
Nice work with that camera. Wow, you got your hands on one of those cameras! Those things can be very handy in factories for finding electrical problems.
That is one nice bike!!!! That bike is sweeeet!

So... is the production of a 50cc head out of the picture? No, it's not. I still want to make 50 cc heads for purists like yourself who would rather not try to sneak around the rules. I believe you are not the only one. I just need to get a little breathing room. I've got to finish production of the current head, plus a short run of twin plug 66cc heads. There are a few other projects other than that which is competing for my time.
I just made a pretty cool looking muffler for my bike, and thought of doing a small run of those mufflers. I also have some other non-bike related jobs looming in my near future, so I can't say when I'll get some 50 cc heads out there, but one would look so cool on that black bike of yours. It would almost be worth doing a run of those heads just to see it on your bike! I'm laughing, but also partially serious!

Well, although I have never taken any temperature readings, it's pretty clear that the CR Machine heads have more cooling surface area. My test bike engine always seems to have a nice temperature (feeling by hand), even after a super hard drive. And I no longer see the rapid cylinder wear I used to get when I ran the stock heads.

Again, nice work on the bikes!

-Fred

 

[Harold_B]

Thanks Fred. Your intake looks good eh? Engine runs better because of it too. The camera is really handy in our lab for thermal studies. We use it for LED and laser stability work mostly. I'm glad you're busy then most likely you'll be around for a for a while. I'll keep my eyes open for a post from you when you get around to the 50cc parts.

Thanks for the feedback on the bike. I can really appreciate the desire to make this a business but I'd starve to death. Maybe I could make up for my losses in volume!