do all speedometer gear units interchange?

[beachbum3478]

i was wondering if all of the speedometer gear boxes down on the front axles are the same. or at least if the ones from 1982 interchange with the different model bikes. bike bandit lists different part #'s but it doesnt make sense why they wouldnt swap out. any ideas? thanks.

[SqDancerLynn1]

Main thing is the different wheel sizes have different speedo drives

[beachbum3478]

oh yea didnt even think of that, so do you think if another model bike with the same tire size would have the same speedometer gear?

[Busafied]

If the tire sizes are the same the ratio is the same

[waterman]

There are not all alike. If the part numbers are the same, same part. If different, doubt they will work. The difference I have noted is that some speedo drives have a larger diameter lip (mostly L models) while the g models utilize a slightly smaller diameter lipless design. The gear ratios may very well be same but they don't interchange. There does seem to be a little correlation within models, the g models seem to be interchangeable, my brother's 1000g is using a 650g drive. However the 650gl unit I picked up to replace the one I gave away, will not fit.

If buying secondhand, try to get a good description of what bike it came from and if not total sure, get a good picture of the inner (guts) side. On the larger L style, there is more space between the outer lip edge and the teeth that engage the wheel. On the g model the teeth are closer. I know it is hard to tell from some pics, but take a close look and you can tell. I will see if I can get some pics to show difference.

[waterman]

Here are a couple examples. The first is what I call the lipped design.

http://cgi.ebay.com/ebaymotors/Suzuki-GS750-GS750G-81-Speedometer-Drive-Gear-074789_W0QQcmdZViewItemQQ_trkparmsZ72Q3a570Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem300272800208QQitemZ300272800208QQptZMotorcyclesQ5fPartsQ5fAccessories

This next one doesn't show you the guts, which is too bad since that is where they wear out. It is of the lipless design typical of the g model. Hopefully you can see the difference. I couldn't find a good pic of the inside guts of this style so you could compare the two. As normal on ebay, I find the majority of the drives are lipped type.

http://cgi.ebay.com/ebaymotors/Speedometer-Drive-1979-Suzuki-GS850-GS-850_W0QQcmdZViewItemQQitemZ250327590987QQptZMotorcyclesQ5fPartsQ5fAccessories

[Steve]

Another difference can be between the L and non-L models. Most, if not all, of the L models (and a few non-L models) have leading-axle forks. The tabs on the speedo drive units that keep them from rotating might be in a different location than the tabs on the ones used on straight forks.

I don't think the drive unit on my wife's 850L is the correct one, but it works. It's kinda hard to see in this photo, but if you look closely, you can almost tell that the cable leaves the axle pointing rather downward, to about the 5 o'clock position. It's been on there about 3 years and 15,000 miles and the speedo is frighteningly accurate, so I have no plans to change it.



.

[Old Colt]

One of the things I look at in speedo drives is the wheel style it came from.
I have not measured if there is a different thickness between leading axle and straight forks, this might relate to the two styles referred to previously.
There are no locating tabs for the speedo drive that I have seen. The cable outlet should be clocked during assembly and is located by tightening the axle.
Later drives that I find on 17" wheels have a different cable end. I do not know when that change was, I expect with the wheel change.

[beachbum3478]

thanks for the replys everyone. im curious though, waterman you were saying about how the L bikes and G bikes have different styles speedo gears, haha so what does my bike have if its a 82 GS1100 GL? thanks.

[Old Colt]

thanks for the replys everyone. im curious though, waterman you were saying about how the L bikes and G bikes have different styles speedo gears, haha so what does my bike have if its a 82 GS1100 GL? thanks.

Does it have leading axle or straight forks?

[beachbum3478]

its got leading axle im pretty sure. its the same kind of forks in the picture of the gs850 above.

[waterman]

thanks for the replys everyone. im curious though, waterman you were saying about how the L bikes and G bikes have different styles speedo gears, haha so what does my bike have if its a 82 GS1100 GL? thanks.

So you laugh at your L model also. Sorry couldn't resist. The L is an L whether it is chain or shaft. You need the lipped style like this:

http://cgi.ebay.com/ebaymotors/Suzuki-GS750-GS750G-81-Speedometer-Drive-Gear-074789_W0QQcmdZViewItemQQ_trkparmsZ72Q3a570Q7c66Q3a2Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318Q7c301Q3a1Q7c293Q3a1Q7c294Q3a50QQ_trksidZp3286Q2ec0Q2em14QQhashZitem300272800208QQitemZ300272800208QQptZMotorcyclesQ5fPartsQ5fAccessories