chain tightening then loosening

[tahoethumper]

So, I'm experiencing an issue that I can't seem to find a positive solution for- it's definitely leaving me a bit perplexed. While my bike is on a center stand and in neutral, I spin the rear wheel (either direction) and notice the chain tightens and loosens, and moves up and down dramatically. What's getting me is that the engine has been rebuilt using new bearings (obviously), the countershaft is true and not bent, the rear sprocket was replaced with a new Strictly Hodaka dished 52T, the countershaft sprocket is not new but shows no sign of lateral/radial run-out, the rear wheel was completely rebuilt using new bearings, and there is a brand new 420 chain installed. The chain is clip-on master link type, and not a riveted type, btw. Is it possible that I was sold a bad chain that has tight/loose spots in it already? All help and suggestions are greatly appreciated. Thanks.

[Dale]

Carefully mark both sprockets and the chain showing where the tight spots are. Then remove the chain and re-install it rotated 180 degrees. Check again for tightness. Further test by rotating each sprocket 180 degrees. You should be able to isolate the culprit. If nothing changes, then I would suspect that at least one of the 3 items is of a different pitch than the other 2 items.

[Zyx]

May we assume the rear sprocket has no visible runout when spinning free?

How many times does it go tight for every revolution of the rear sprocket?

[Charlie R]

I'm gonna guess that the four bolt hub that that the early 90,100,and SR used is bent. I have had several over the years that I had to pitch for that reason. By design the hubs were poorly designed. Could possibly be loose wheel bearings as well. The bearing bores elongated (again to do more bad design).

Charlie R.

[michael_perrett]

I found out that some new sprockets are not stamped out correctly and show signs of what you are describing. Not much you can do about it without a lot of work on modifying the sprocket. My new rear sprocket for my Ducati was off center slightly. I don't like it, but will do the "ton" without any problem.
Mike Perrett

[Charlie R]

After re-reading my earlier post I must apologize. I wrote with the eloquence of a Nigerian scammer.

TT, do you have a truing stand? If the rim itself is noticeably moving up and down, I would bet 33 cents that the hub is bent. It is so common with the 4 bolt hubs that I won't even clean the hub for re-use until I've spun it on the lathe for concentricity.

Charlie R.

[Zyx]

For the moment I am still using my original four bolt non-cushioned hub behind a 97 Super Combat engine with no real issues. However --- I know for a fact that the bearings do not stay tight and true in this hub because the bearing boss elongates over time due to the shock from the lack of cushioning. Whether it draws the chain because of this I have not detected because I run the chain so that it is not tight at the swing arms furthest reach, but instead let the chain rollers do their work. I am replacing the four bolt hub very soon with the later design six bolt cushion hub, just for insurance.

I would expect, however, that if either the bearing bosses or the sprocket bolt holes are distorted, you will see this by spinning the rear wheel, chain off, wheel free, because the hub, centered or not, will wander or the sprocket will.

If the bearings are not tight in the hub, they can be tightened, but it won't last forever. If the sprocket is off center due to bolt hole elongation, this too can be bandaid fixed by loosening the bolts and adjusting the sprocket until it does not run out, then tightening the bolts. If the holes are so loose that such adjustment won't hold, either set the bolts in epoxy and true, or toss the hub. If the sprocket dish is bent, which it could be, it will also wobble side to side as well as running out in line with the drive. Easy to see, hard to fix. Even though they are scarce, a new one is better than trying to re true a bent sprocket. And anyway, sprockets are a consumable product. If it got bent it took a heck of a hit, and so did the hub.

The only other thing that comes to mind is a chain with a stiff spot in it. Even though new, flex every link to be sure none are jammed up.

[tahoethumper]

As always, some great input from everyone. When I get a free moment I will check further into how true the rear wheel hub is. When I laced and trued the wheels, I do remember seeing a slight bobbing up and down that I was unable to get rid of (hell, the wheels are older than I am so I just went with it). I have a strong suspicion that it is in fact the rear hub. Again, contershaft sprocket is sound, along with new rear sprocket and new chain. Thanks again all!

[tahoethumper]

Well, it seems Charlie R is right. I do believe the holes that the 4 sprocket bolts thread into are slightly elongated. My next question for all of you is if it's possible to replace a super rat hub with an Ace 100 B hub(with the cush drive)? I came across an Ace 100 B hub with a 4 bolt pattern - similar to my super rat hub. When i tried mocking the newly found rim/hub on to the swing arm, i can't seem to get it perfectly centered within the swing arm. Hopefully im not confusing everyone with this. Here are some pics of what im dealing with. The super rat hub is on the wheel with the mounted tire. Thanks.

[Zyx]

93 Super Rat and 100B use the same four bolt non-cushioned hub. The 100B+ used the cushioned six bolt hub. You should be able to install just about any Hodaka wheel assembly on your bike but may need to adjust the spacers, and later hubs used a larger diameter axle, requiring that you open up the slot in the swing arm. You will have to match sprockets to the same chain size. Early bikes used 420, later used 428. One of the in between rats used 423.

When you say you can't get "it" centered in the swing arm, which "it" do you mean? Hub and rim? If so they don't center but are offset to the right away from the chain. When done it is the two sprockets that have to line up, and when they do, the rear and front tires should also line up. The rear tire will roughly center under the rear hoop. The rim will center between the right arm of the swing arm and the chain.

[tahoethumper]

Thanks AZ Shorty. By "it," i meant getting the rim centered between both sides of the swingarm. I wasnt aware that it is supposed to be slightly offset. Also, the hub im testing to see if it works is a cushioned hub with a 4 bolt mounted sprocket - any idea what model this pertains to?

[Zyx]

Not offhand. Unless the B+ had some that were four bolt, but I don't personally know. Maybe Paul or one of the others who were dealers would know this one.

[dirty_rat]

Can you post some pictures of the wheel/hub alone, and from both sides. I don't think Hodaka ever had a 4 bolt cushioned hub, but I know some Honda's did. A picture will give a better idea. Also, the Honda hubs often had the Honda wing stamped inside the brake area.

[taber hodaka]

I am running a webco cush hub/sprocket on my ace 90. Clarence

[tahoethumper]

Here are some pics of the hub i came across (if anyone might know what type it is? ). It did come off an old Hodaka.

[Zyx]

Not a Hodaka part, whatever it is. It took a licking. I believe all the Hodaka sprockets in four bolt were dished in order to place the plane of the sprocket in proper line with the CS sprocket.

Clarence, is this what your Webco unit looks like?

[Bullfrog]

I too don't know what hub it is, but I do know what it isn't. It isn't a Hodaka hub.

Ed

[hodakamax]

AZ, I also have the cushioned sprocket on my old short tracker, I'll try to get a shot of it tomorrow if I can get to it. (I'll have to get the ladder out, but I have to change some bulbs anyway).

Max

[tahoethumper]

Thanks a lot guys. Well, now to find a decent hub and relace my wheel.

[Charlie R]

Won't swear to it but that wheel/hub set up looks like an early small bore Kawasaki. Maybe a KE or KS 100. Just my .02 cents worth.

[Zyx]

Could be. The tensioners look really familiar, like '60's Honda step-through 90.

[hodakamax]

AZ, here's a shot of the Webco cushioned sprocket. At least I think I ordered it from them. The sprocket was bolted between two plates with grommets in corresponding holes. It worked fairly well and was all we had at the time. I would like to have shot it from the other side but I needed a ladder which is outside in the rain.

Maxie

Hmm, looks like I need to dust the old short tracker!

[Zyx]

Looks like a Hodaka hub with a drive adapter. Clearly different from the one in the photos above.

[rtboone]

Greetings

I bet a few hot laps around the block would clean those pesky, dusty cobwebs! Just be careful, those old tires might be a little bit greasy in the rain.

Tom

[hodakamax]

Hey Tom, I would have to push it around the block, it has no tranny or crank! I'm still gathering parts to rebuild the engine for some unknown reason. I sold the bike decades ago and decided I needed it back. When I found it years later the engine was all apart and the close-ratio 5-speed was lost. I found a NOS CR tranny the other day along with a usable crank. I think it's found a final home as a display model but it does need to be complete.

Max

PS--You've probably read about the complicated history of this bike in Vol. 2 #16 Resonator, if not check it out. (Just one more reason to join the Hodaka Club! Tom and I are members.)