Model 97/98 Clutch pinion gear

[bradocross]

New ones are not available so I'm looking for a used one in good shape. Thanks for your help!

[hodakamax]

Me too. #954001 also fits Model 95. I'm trying to find one to convert my 94A to straight cut gears but you can have the first one we find, It's your post!

Max

[bradocross]

Thanks Max!

[dcooke007]

Hey Brad, do you not have the pinion gear or is it worn / damaged? I know many of these are replaced due to scoring on the inner bore. Since these are starting to get scarce I am wondering if the inner bore could be refinished. My thoughts are to precision hone the bore to remove the scoring and may be hard chrome to restore diameter. If the scoring is minor honing to remove high spots might be all that is required.

Danny

[bradocross]

Danny,

The control shaft ball receiver shatter and took a trip through the clutch side of my motor. The damage done to the teeth is irreparable. I also lost the primary gear and the clutch hub, etc. Unfortunately, without a replacement pinion gear my little Hodaka will have to sit in the corner for awhile.

[dcooke007]

Hate it when that happens. Hopefully someone will be able to help you out.

Danny

[Zyx]

Is the aspect shown the worst of the damage or at least typical of what it looks like all around? Are any of the teeth actually cracked, or just mashed as shown? I am thinking that the tooth profile is damaged only in a narrow band, and only toward the outer tip of the tooth. Most of the force of power transmission occurs in the fatter part of the tooth, and the thinner part that is damaged is just a ramp- on, ramp-off to engage tooth to tooth as it rotates. Dress the teeth down with a fine file so that the working surface has no bumps, and leave the gouge where it is. I don't mean to shorten the teeth, but to smooth out the displaced metal from the sliding face of the tooth. As long as they are not cracked, it may yet work, although I would much prefer a new gear, of course. Gear teeth are work hardened, so it might take a really good fine warding file, or a diamond file, which is more generally sold for sharpening knives. If all else fails, w/d sandpaper wrapped around a thin file or strip of metal for rigidity. Dress it to the point that viewed side on, you can't see any extrusions.

If you can't find a pinion, it might be worth a try.

[hodakamax]

Rather than retiring the bike you can put the Model 94 helical gear set in. It looks like Paul has the 944502 in stock but not the 944001 pinion gear. There's usually some of these on Ebay. This was discussed a few pages back under " Straight cut vs Helical''. You might check for comparing the two. Probably the major differences are that the strait cuts are stronger and make more noise than the helical ones. Hopes this helps!

We can't be parking a Hodaka!

Max

[bradocross]

GMc
The picture doesn't do it justice as the other side has a tooth broken off, so it's toast.

Max
I think I'll wait to see if I can replace "like kind". If nothing surfaces then I'll rethink going helical/straight cut. Thanks for the suggestion!

[Zyx]

If it broke a tooth, it is done, and may be out of round anyway from taking the hit. Finding parts on eBay can work and can also end up being like a snipe hunt. Most guys on eBay don't know what the heck they have, so you can trust descriptions. Someone out there may have used 97 parts that can help. If I remember right, the 94 has the same primary ratio and helicals are no crime. Something close to the ration may work also. Maybe Combat Wombat?

[Zyx]

All the primaries are I believe 1.75 module, so the later 125 gears are no stronger than the earlier 100B primaries. As an exercise in what you can do to work around the issue, you could settle for a higher primary ratio from a Super Rat 100 for example, and change your final drive sprocket to a smaller one to adjust the overal ratio back to normal. If you can't find the gear you want, there are other ways.

[gilligan98]

Is this the part you are looking for? They have a little surface rust but no cracks or broken teeth.

[hodakamax]

They appear to be for the 93 Super Rat just by looking at the lugs. I just measured the inside diameter at .745 inches for the 93.

Max

[gilligan98]

Thanks,
They were in a box of parts I got that were labeled Super Combat.

[Charlie R]

Pinion gear for 97/98 is 21 T spur. Pinion gear for 93 is 17T spur.

[Zyx]

Gilligan,

Regarding the pinions shown, what is the tooth count?

[gilligan98]

These both have 17 teeth.

[Zyx]

There you go. Not 97/98. Lots of folks take bikes apart not knowing what they are, and think all Hodakas had the same name. A guy at the local Honda shop last week swore that he used to have a 1965 Super Scat, chrome tank, red frame and all. You can't argue with other people's reality.

Charlie is right. Only the 93 series had 17T spur cut pinion gear. Max, your eyes are better than mine if you could spot the application from a side view photo. Correct call.

[Zyx]

Danny,

The control shaft ball receiver shatter and took a trip through the clutch side of my motor. The damage done to the teeth is irreparable. I also lost the primary gear and the clutch hub, etc. Unfortunately, without a replacement pinion gear my little Hodaka will have to sit in the corner for awhile.

Probably, the retaining circlip was not entirely installed, and popped out, letting the springs and ball loose under the clutch cover. The engine I purchased on eBay last fall was this way. 3/4 of the circlp was in the groove, the rest not, and at a glance, it looked like it was installed because all the parts were held in place. As long as pressure stays on the clip, the clip stays in place. But start shifting under pressure and just for a moment, the spring pressure shifts and let's the circlip pop out. Parts shoot into the cover and there you go. I actually rode mine this way for an hour, and didn't catch the error until yesterday when I pulled the control shaft to install a new o-ring in the countershaft. Glad I caught it before it let go.

I have had to trim every new circlp I have used (including the new one yesterday) so that when fully compressed into its place, the clip wire was short enough to pack into place. As made, the clips do not fully compress and the wire ends would have to bypass each other a bit to get all the way into the groove with the retainer cup all the way over the clip. Which they can't do for lack of space. I had to remove about 1/32" of wire length to get them to fit the hole. But as long as some part of the clip is in the groove, the stopper is help back and it looks as if it is installed when it isn't. Properly seated, the circlip entirely disappears into the retainer cup.

Something to watch for. Some parts need to be hand fit, even when using OE new parts. I am also thinking that had the ball receiver actually shattered in place, it would have stayed inside the counter shaft. There is very little room for parts to bypass the spring stopper. That's why I surmise the clip let go and dumped the ball and springs into the side case.

[Bullfrog]

I think Arizona has the timeline correct when he suggests that the ball receiver came off the end of the control shaft and then was chewed up/shattered by going through the gears. I've never, ever, heard of a ball receiver shattering due to pressure from the counter shaft balls. The ball receiver is quite purposely NOT a hardened item. It is intended to be tough but not brittle.

However, I've also never seen a control shaft circlip which was too long to fit in its groove properly and thereby caused the retainer to not be able to move "out" far enough to fully contain the circlip. Arizona says he's seen it and fixed it (apparently multiple times). I can't debate that. However, I've seen LOTS of circlip retainers which were not full seated "out" over the circlip when the job was deemed to be done. In EVERY one of those situations which I have observed (where "un-digested" original parts were found inside the engine), the parts were correctly made. The error was procedural, ie the mechanic did not make sure the circlip was fully seated inside the retainer before proceeding to close up the engine and run it.

My 2 cents,
Ed

[BrianZ]

The late model control shaft has a smaller diameter and hence smaller diameter clip than the earlier control shaft. AZ, any chance you were putting the early model "larger" clip onto the later model control shaft? The later model control shaft assembly will work on earlier models, so there is a good chance that they could have ended up replacing the early model control shaft assembly as an "upgrade".

Brian

[Zyx]

No telling. I bought this one blind on eBay. Everything else was screwy. Why not this too? Aside from two sizes, it is still important to verify that the clip is fully seated and buried in the cup or it can pop out.

The engine I am working on is a 97. So says the motor number. The piston and cylinder look right. Carb is a 32. After that, it got weird. The clutch was a 97 body with a 100MX disc count inside. Boy did it slip. Primaries are right for a 97, but the trans gears were 100MX or 100B. So who knows which control shaft it has or which countershaft for that matter. I don't know. I do know that the new clips I ordered were part number 904620A, but I will have to look that up to say which generation of engine that goes with. I thought 97, but I could have done something else. Only Paul could say whether he stocks two sizes of clip. Since it is easy to trim, it hardly matters as long as it fits one way or the other.

[Zyx]

Just looked. The "A" suffix goes with the 97. If those are larger and needed trimming, sounds like I have an earlier control shaft as well. Long as it works.

[Bullfrog]

The diameter difference between the Ace 90 thru model 97 control shaft and the Model 98 and later control shaft is large enough that I don't think you could trim a large circlip to fit the smaller 98 control shaft without also doing some significant "re-forming" of its shape. Without "re-forming" it would slip on the smaller shaft without trying to "hug" the shaft (much less the groove it needs to fit into).

So it is pretty hard to mix components from the two types of control shaft.

Ed

[Zyx]

Actually, it is simple to reform the clip. First, the circlip is not spring steel, or if it is, I am not impressed. I think you could make one out of iron wire. Secondly, the difference is slight between smaller and larger units. I didn't actually measure the amount I trimmed off, but would guess half a millimeter or a bit less. Circumference being pi times diameter, a half millimeter in circumference is a sixth part of a millimeter in diameter, which is a very small difference. The idea is that it has to be short enough that when conforming to either the shaft groove as a minimum circumference, or the retainer cup as a maximum circumference, the wire ends don't overlap. The A suffix part does not fit in the smaller cup without trimming. Just did it yesterday, so memory is fresh.

But I would expect the smaller ring, if it is smaller in circumference but not smaller in wire gauge, to work in either or any combination of parts. The circlip needs to prevent the retainer from bypassing the clip. It does not need to be full circumference to do this. So even if a smaller circumference clip is used, it will fill 7/8 ths of the groove which is more than it needs to work. Actually, any thing more than 50% will do it because of tolerances although I don't suggest this as anything other than a field fix. It does not need to hug the shaft to work. It needs to bridge the gap between groove and retainer cup inside circumference. The diameter of the wire from which the clip is formed does this without spring action. Once installed and trapped, there is nowhere for it to go. The trap is made up by wire gauge, not full circumference. If the clip is thick enough to fit the groove, any length less than 101% and more than perhaps 85% is going to be fine.

Main point though was that even with the right part, wrong assembly leads to failure of the clip, as noted by Ed. I agree.