HF 79cc with EZM clutch centermount build - how to gear lower

GoldenMotor.com

chrisnbush

New Member
Jan 10, 2008
41
0
0
Richmond, NH
By the way -

I threw the crappy plastic bolts that hold the EZM transmission cover on when I opened the shipping box. Yeah, those are going to last. I knew how much I would need to be in and out of the thing to get it right, for where I live, the speed and power I want, etc.

I just drop two small short bolts in the top 2 holes and shoot a spot of 50 year silicone on the heads to keep them in place. I keep a caulking gun with a tube of the stuff sealed with a big nail. The most useful stuff on the planet, along with gorilla type for repair of rain suits...

cb
 

scotto-

Custom 4-Stroke Bike Builder
Jun 3, 2010
6,505
24
38
Ridin' inSane Diego, CA.
I've been working on my EZM all weekend trying to replace the belt and get it all back together. Taking apart the EZM is by far the most difficult and tedious thing to do on my bike. My first time took me an hour, second time about 40 minutes, third time about 25 minutes. I thought my belt needed to be replaced, so I got the AX25, later to realize I have the newer model EZM with the 2'' pulley, so it was too big. I read the AX24 is too small for the 2'' pulley, so I ended up putting back on my old one so I can ride it for the time being. As I put on the old belt and got all the screws tightened up, one of them snapped in half. So then I took it all apart again, went to the hardware store and got new bolts to go back in it. So now I'm back to square one, what a waste of time! I have a 79cc HF motor waiting to be installed, it looks like I might need a different belt. Also, after I took everything apart and reinstalled, I lost acceleration and top speed. I have the belt as tight as it can go ( the EZM is shifted as far back as it can go from the crank shaft). Not sure if I need a new belt or not at this point. It has about 1000 miles on it.
All that work for nothing? Did you ride today? The AX25 is the belt for most applications using the EZM tranny, trust me. ;)
 

chrisnbush

New Member
Jan 10, 2008
41
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0
Richmond, NH
Yes, but you can't use the lower range, if you open up that pulley even a bit, the side of the belt will start slaping on the aluminum of the transmission housing.

I went to an AX25, which gets me down to 2.5" about, but too much more, and THIS one will slap.

I tried and AX24 but that is too small with the adustment out to what would be 2.1". I think the pulley is good to about 2" before the cogged part starts making contact.

I am kind of fussy about getting what I want - I am seeing AX 24.5 belts out there, might try one. A better solution might be if EZM where to widen the transmission plate like about 0.5 inches at the bottom, as long as it doesn't interfere with the motor mount.

I want to be able to use the entire range with the same belt.

:)
 

jim71

New Member
Jun 13, 2013
63
0
0
pa
ahhh nice thread!
that motor sits in there nice!!! I like it!
you can still pedal it ?
and that ez thing is pretty cool,but I wonder why they didn't make the belt ride on top of it instead of under?
does that motor have too much power for that system?
di you look into the torque converter? too big? I see the shaft size is 3/4 is the motor shaft 5/8? http://www.ombwarehouse.com/Torque-Converters/

just wondering , new around here and trying to get something going ..
 

Desert Rat

New Member
Jul 30, 2012
565
9
0
Apache Junctoin Az
I use the AX26 with the adjustable pulley
(mine is turned all the way in, so I think it is at 3.1")
the 25 is for the 49cc version AFAIK
Hey azBill
I not Bi**** but if you look at my pics on page 2 you can clearly see
that if I open my pulley any more than that it's hitting the frame
and yes I to would like to be able to use the full range,
if you're not going to use the full range then why bother
with the adjustable at all?
not mad and can buy the belt at many places

For the OP
a suggestion I haven't tried yet (other than on a car) to get the accurate size you need
is at autozone for about six bucks or so it's an emergency belt with clamp
should be able to use it to get the accurate size you would need
I've been side tracked with a new 66cc
Oh and how did the belt dressing work?
 
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Desert Rat

New Member
Jul 30, 2012
565
9
0
Apache Junctoin Az
And one thing I've been toying with the idea of
Removing the idler and using a suicide type lever to engage it by putting idler
on that from underneath the belt, Possible????
and yes bill I know you said the belt would crack
I'm a machinist with tools, already I have taken the arm plate over the belt
off just to see, 15 minute job no problem can do that on the road.
 

chrisnbush

New Member
Jan 10, 2008
41
0
0
Richmond, NH
Wondering why you guys are so keen on pulling the damn belt down. Would it provide more friction at the drive pulley or something ? Going down makes it worse for adjustable drive folks I think, as at least going up keeps it away from slapping on the plate - allows you to use a wider range of adjustable pulley settings.
 

jim71

New Member
Jun 13, 2013
63
0
0
pa
jpg.gif QMatic-drivetrain-view-e1367474773743.jpg (24.8 KB)

see now this one looks right
I just looked on u-tube and they revised the setup or something ,because on the newer one its like the way you had it , but the older one is the way I sent the picture it is.. weird !
I would try and put it they way it looks in the picture I sent ..
or call them ,
 

azbill

Active Member
May 18, 2008
3,358
5
38
63
Fountain Hills, Arizona
the old style (pulling belt up) was causing premature belt cracking,,,
belts last much longer when using the newer style ;)

that was while using the 2" pulley,,,it might not be so bad using the 3" one tho
 

jim71

New Member
Jun 13, 2013
63
0
0
pa
the old style (pulling belt up) was causing premature belt cracking,,,
belts last much longer when using the newer style ;)

that was while using the 2" pulley,,,it might not be so bad using the 3" one tho
I guess too much angle?
I think I like the old style better ,id rather change it every so often rather then it banging on the bracket ,
I think im gona order one of them kits today ,600.00 bucks is a lot of money hopefully them hs motors are decent ?
 

zean

Active Member
Dec 5, 2010
321
216
43
california
Hi. Excuse me. With the belt slapping on the plate, couldn't you slot the holes very slightly on the main drive plate then move the plate to tightened the belt? If you slotted the holes 1/16th of an inch and adjusted the backing plate wouldn't that tightened the belt @ 1/16th inch on the top of the belt and @ 1/16th inch on the bottom of the belt where the drive pulley is and therefore give you @ 1/8 inch total belt tightening? Thankyou.
 

chrisnbush

New Member
Jan 10, 2008
41
0
0
Richmond, NH
For the slippage have you thought about dressing your belt?
Hey just an update. I got some belt dressing, I chose the Sprayon Belt Dressing product, as it claimed to increase grip up to 50%. I applied it to the belt I had on, an AX 25 I don't know the manufacturer. Anyway, it quieted the belt a good bit but did absolutely nothing for grip. I had 1200 miles on the belt.

So anyways I got a new belt, went with a Gates belt as people on the web say they are good. It is better with this belt now, so I guess my previous one had worn somewhat.

Just FYI, in my hands belt dressing isn't increasing grip. I probably will use it from time to time as it does quiet things down a abit.

cb