Author Topic: Convert Rear Drive on a G5  (Read 2994 times)

Offline ozarquebus

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Convert Rear Drive on a G5
« on: August 29, 2019, 11:30:21 PM »
I have a 78 Convert parts bike and I was thinking of putting that rear end on a G5 to achieve a higher gear ratio.
Is this a doable plan?
 I do not know if it will even fit and do not know if what the Convert ratio is, but I think it will be higher.
« Last Edit: August 29, 2019, 11:31:04 PM by ozarquebus »
John

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Online Antietam Classic Cycle

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Re: Convert Rear Drive on a G5
« Reply #1 on: August 30, 2019, 03:06:19 PM »
The stock G5 gearing is 7/33 which works out to a 4.714 to 1 ratio. The Convert gears are 9/34 which works out to a 3.777 to 1 ratio. Quite a bit higher, so much so that I doubt it will work well. It would be like taking off from a standing start in 2nd or 3rd gear.

Then there's the incompatibility in the splines: G5 input is 10 splines, the Convert is 20 splines. That could be solved with this driveshaft:
http://www.mgcycle.com/index.php?main_page=product_info&cPath=35&products_id=5298

If you want higher gearing on the G5, an 8/33 rear drive from a Cal 1100/EV series would be a more workable solution. That ratio is 4.125 to 1, so a usable amount "taller" than the stock 7/33 without going overboard.
Charlie

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Re: Convert Rear Drive on a G5
« Reply #2 on: August 30, 2019, 05:26:41 PM »
I have a 78 Convert parts bike and I was thinking of putting that rear end on a G5 to achieve a higher gear ratio.
Is this a doable plan?
 I do not know if it will even fit and do not know if what the Convert ratio is, but I think it will be higher.

If you want to swap the 7/33 for an 8/33 I'd be happy to do it as I need a 7/33 for my outfit.

Having said that I would counsel against it as I experimented with various ratios back in the 80's on both a stock SP and various hot-rods and always came back to the 7/33 as the best option.

Pete

Offline ozarquebus

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Re: Convert Rear Drive on a G5
« Reply #3 on: August 30, 2019, 07:18:00 PM »
Thanks for the input, that pretty well sums it up right there, from the sound of it.
Since the rear end on hand would not work, then I doubt I will try to find an alternative just for experimentation.
Thanks
John

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Offline earemike

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Re: Convert Rear Drive on a G5
« Reply #4 on: August 31, 2019, 08:07:07 AM »
Didn’t they call em moon gears? Not practical for most applications...
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