Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

[Don S]

Here are a some documents I put together that might come in handy for those trying to figure out what gear ratios they have in their MC-1 through Alpha I Gen II outdrives.

It used to be commonly thought that the gear ratio only changed in the uppers, and all the lowers were the same. This if far from fact as you will see.

For the upper View attachment Upper ratio.pdf (Replaced 11/28. Original had mistakes in it.)

For the lower View attachment Lower Ratio.pdf

Some more ID and ratio information to go with the above.

View attachment Gear Ratio ID.pdf

 

[cr2k]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

Thanks, Don for posting those!

 

[FLAT RATE]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

Thanks Don.

 

[achris]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

To summarise the summary of the summary...

(For MC-1 and later) There are 3 different lowers (13:21, 14:28 and 17:28). These can be matched up to any of the 5 different uppers (17:19, 20:24, 22:20, 20:16 and 24:24), although some combinations are not used. Also note that the 13:21 and 17:28 lowers are very close in ratio (less than 2% difference). The 13:21 was introduced to 'reduce gear noise' apparent in the 17:28.

Cheers and great effort Don.

Chris........

 

[MarkSee]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

To summarise the summary of the summary...
(13:21, 14:28 and 17:28) (17:19, 20:24, 22:20, 20:16 and 24:24) 13:21 and 17:28 ..3:21 was introduced to 'reduce gear noise'..

Indeed very nice documents; and able to save them for future reference. Thanks Don.

Some of these "ratios" remind me of my pants (waist/length) sizes when I was like.....10.....

To bad though that as the years have gone by, the first number in the ratio seems to have grown at a much greater rate than the second number of the ratio.... ...but maybe that's nature way of "reducing my gear noise"....

Mark

 

[wca_tim]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

Are you sure all the columns in the first table are correct? You may have a typo... the 1.84 ratio for 83-90 should be 17 - 19 shouldn't it? and the line below it, maybe 1.65 should be 24 - 24? and alphw one gen 2 1.65/1.62 24 - 24?

Also, I wouldn't be surprised if the lower change also had something to do with strength and set up tolerances... larger, stronger teeth which are not quite as sensitive to shimming being perfect as the smaller ones in the earlier lower gear set...

 

[Don S]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

Good catch, I fixed them and replaced the file.
Thanks.

 

[wca_tim]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

Good catch, I fixed them and replaced the file.
Thanks.

nope, Thank YOU for putting them all in one easy place. Seems whenever I need to compare some of the parts and pieces I'm playing with on another project (or a broken one from before), I'm digging around looking for these...

 

[achris]

Re: Gear Ratio Information for MC-1 thru Alpha I Gen II Drives

nope, Thank YOU for putting them all in one easy place. Seems whenever I need to compare some of the parts and pieces I'm playing with on another project (or a broken one from before), I'm digging around looking for these...

+1 on the thanks... I save them all to an nice little folder on computer called 'Dons tips'...

 

[mattinthebox]

Links are broken.
If someone can fix or re-up the pdf's it would be much appreciated.
Thanks in advance...

 

[jbcurt00]

I just tried them all

All the links downloaded and opened w expected content.

closed