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AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 10:20 am
by Duke
So I ordered a couple of cogged Goodyear AX24's off amazon and I can't get them to work on my SB50's. It rides too high on the rear pulley and drags on the gearcase inside. I tried getting it into the groove by spreading the pulley halves but they come back together pushing the belt out. Am I doing something wrong? I guess I am realizing now these aren't a DIRECT replacement for the Honda Bando as they are wider. Does that mean a higher top speed with a slower takeoff? Because the takeoff is slow enough as it is...
Also wondering about how the rear pulley functions on these. Is it supposed to squeeze the belt and keep it in the same position or does is vary with speed like a variated pulley. Anyone care to elaborate???
Anyway here's a pic of my latest acquisition. 1-owner, 1600 original miles :D

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 2:32 pm
by abreen89
i too ordered a ax 24 off of amazon and it rubbed... pathsoundsguy has had success with the ax24 he order from grainger.com i think im going to order that one and try it. The ax24 is a wider belt making your buttom end a little slower but giving your top end a few more mph...

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 2:42 pm
by abreen89
this is the one i bought that rubbed http://www.amazon.com/dp/B004HFRW6O/ref=biss_dp_t_asn

this is the one pathsoundguy bought and it worked for him http://www.grainger.com/Grainger/DAYTON ... Pid=search

im not seeing any difference in dimmensions so im not sure... but mine too rides way high on the pulley and just rubbed the whole time...

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 5:02 pm
by patthesoundguy
are the scooters variated that the belts are going on? My spree was a bolt on and go operation. Im figuring that the ax24 might just be a little too long to have the tension needed to keep the belt riding low enough in the driven pulley on the scoots you are trying them on. There is not much else that can be wrong to make the belt ride too high, that I can think of.

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 5:10 pm
by abreen89
patthesoundguy wrote:are the scooters variated that the belts are going on? My spree was a bolt on and go operation. Im figuring that the ax24 might just be a little too long to have the tension needed to keep the belt riding low enough in the driven pulley on the scoots you are trying them on. There is not much else that can be wrong to make the belt ride too high, that I can think of.
no the sb50p duke is trying and the honda spree i am trying are both NON variated and mostly identical to your engine the only conclusion i can come up with is that the belt on amazon is some how different then the grainger???

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 5:44 pm
by Duke
Looks like I will be ordering a couple of Bandos... :oops:

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 9:57 pm
by abreen89
Duke wrote:Looks like I will be ordering a couple of Bandos... :oops:
bandos>?

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 11:04 pm
by zuphilius
abreen89 wrote:
Duke wrote:Looks like I will be ordering a couple of Bandos... :oops:
bandos>?
Stock Honda belts.

Re: AX24 belt on 88 Elite E

Posted: Mon Jul 30, 2012 11:42 pm
by patthesoundguy
abreen89 wrote:
patthesoundguy wrote:are the scooters variated that the belts are going on? My spree was a bolt on and go operation. Im figuring that the ax24 might just be a little too long to have the tension needed to keep the belt riding low enough in the driven pulley on the scoots you are trying them on. There is not much else that can be wrong to make the belt ride too high, that I can think of.
no the sb50p duke is trying and the honda spree i am trying are both NON variated and mostly identical to your engine the only conclusion i can come up with is that the belt on amazon is some how different then the grainger???
Yeah I was just making sure. in the next few days Im going to have my belt cover off to repaint it again Ill have a look and make sure there is nothing Im missing when i have it apart.

Re: AX24 belt on 88 Elite E

Posted: Tue Jul 31, 2012 12:19 am
by az_slynch
Funny, I was just pursuing this issue...

The Dayton AX24 belt measures (according to Grainger...) 5/16" deep, or .3125" inches. I just received a Goodyear AX24 in the mail today, saw this thread, and measured the depth with a set of calipers; it measured between .335" and .340" on ten different tooth samples. My guess is that the Goodyear belt is a bit thicker in the depth dimension. On the thinner samples, it was .020" inches (roughly .5mm), which could be just enough of a difference to rub.

Aside from getting the Daytona belt, the next easiest fix might be to clearance the casing a bit with a file or rotary tool. Here's what I found when I looked at the pulley...

The driven clutch on the SB50P is slightly different than the Spree. Both bikes are fixed gear, but the driven clutches and pulleys are different. I pulled out both units ( I had recently rebuilt an '85 Spree and a '90 Elite E driven clutch) and did a quick "stare and compare" on them. The ramp angles on the SB50P are sharper at the periphery and the compressed pulley is about .015" thinner than the Spree pulley. Don't know how true each of my pulleys are, but I'd consider that to be a possible reason for "belt rides high".

The pulleys wont work like a typical CVT driven clutch. While similar in construction, both of these units use a very stiff spring to prevent the pulley halves from spreading under acceleration loads from the belt. On the SB50, it has a toothed plate that passes though both pulley halves in order to keep them from slipping in relation to one another or pulling apart.

It might be possible to dismantle the driven clutch and insert a few thin shims between the pulley halves, but I don't know if this would cause the belt to ride too loosely. If you wish to experiment, there's a Piaggio tool for moped clutches that works pretty well for assembling and disassembling single-speed Elites and Sprees:

https://www.treatland.tv/olympia-vespa- ... puller.htm

I'll look into this further once I get engine bits back from the machine shop. I was looking at the AX24 mod too as part of an attempt to squeeze a bit more speed out of an SB50P without kitting; it's not my bike and it has to be reliable enough for a new rider and capable of touching 35mph.

Re: AX24 belt on 88 Elite E

Posted: Tue Jul 31, 2012 1:13 am
by abreen89
az_slynch wrote:Funny, I was just pursuing this issue...

The Dayton AX24 belt measures (according to Grainger...) 5/16" deep, or .3125" inches. I just received a Goodyear AX24 in the mail today, saw this thread, and measured the depth with a set of calipers; it measured between .335" and .340" on ten different tooth samples. My guess is that the Goodyear belt is a bit thicker in the depth dimension. On the thinner samples, it was .020" inches (roughly .5mm), which could be just enough of a difference to rub.

Aside from getting the Daytona belt, the next easiest fix might be to clearance the casing a bit with a file or rotary tool. Here's what I found when I looked at the pulley...

The driven clutch on the SB50P is slightly different than the Spree. Both bikes are fixed gear, but the driven clutches and pulleys are different. I pulled out both units ( I had recently rebuilt an '85 Spree and a '90 Elite E driven clutch) and did a quick "stare and compare" on them. The ramp angles on the SB50P are sharper at the periphery and the compressed pulley is about .015" thinner than the Spree pulley. Don't know how true each of my pulleys are, but I'd consider that to be a possible reason for "belt rides high".

The pulleys wont work like a typical CVT driven clutch. While similar in construction, both of these units use a very stiff spring to prevent the pulley halves from spreading under acceleration loads from the belt. On the SB50, it has a toothed plate that passes though both pulley halves in order to keep them from slipping in relation to one another or pulling apart.

It might be possible to dismantle the driven clutch and insert a few thin shims between the pulley halves, but I don't know if this would cause the belt to ride too loosely. If you wish to experiment, there's a Piaggio tool for moped clutches that works pretty well for assembling and disassembling single-speed Elites and Sprees:

https://www.treatland.tv/olympia-vespa- ... puller.htm

I'll look into this further once I get engine bits back from the machine shop. I was looking at the AX24 mod too as part of an attempt to squeeze a bit more speed out of an SB50P without kitting; it's not my bike and it has to be reliable enough for a new rider and capable of touching 35mph.

good info so it sounds like the dayton has more clearence then the good year ill be purchasing a dayton

Re: AX24 belt on 88 Elite E

Posted: Wed Aug 08, 2012 1:12 pm
by Duke
Thanks AZ, that's some informative research right there. I certainly thought about shaving the case a little as there is just one bump at the rear pulley where it rubs. I just wasn't sure how thick the case is back there and just how much clearance that belt would need back there. Do you reckon there is much variance in how high the belt rides in the rear pulley due to different speeds? I am still using the OEM belt which is surely as old as the scoot (88) and it barely reaches 30 mph...

Re: AX24 belt on 88 Elite E

Posted: Thu Aug 09, 2012 4:56 pm
by Bspree
wow i just installed a az24 belt and it works great , my scooter has a 68cc big bore kit and the belt works perfect

Re: AX24 belt on 88 Elite E

Posted: Thu Aug 09, 2012 6:02 pm
by Bear45-70
Bspree wrote:wow i just installed a az24 belt and it works great , my scooter has a 68cc big bore kit and the belt works perfect
The size of the engine has nothing to do with the belt fitting or not.

Re: AX24 belt on 88 Elite E

Posted: Thu Aug 09, 2012 6:06 pm
by abreen89
Bspree wrote:wow i just installed a az24 belt and it works great , my scooter has a 68cc big bore kit and the belt works perfect

what kind of scooter did you install it on and what brand of belt did u get?