Bryan,
I will chime in and share what I learned with my model 94 Wombats. It is confusing...
The 94's were originally equipped with 423 chain (not 420 nor 428). You will find that the countershaft sprockets are listed at 420 and the rear sprockets 423. The 94 chain was originally 423 but this size is rare and 428 is now used. (I still have one bike with the 423 chain).
Now here is where I get lost. I don't know if the different sizes can be mixed. One would think not, but I have heard people talk of running the larger chain on smaller sprockets on purpose... Perhaps others will enlighten us. The key is understanding the difference in the chain sizing and how the pitch is determined. If the difference between 420, 423 and 428 is just width, then the 428 chain is going to roll just fine over the 420, 423 and 428 sprockets. For me, I just order a complete set all at 428. It is best to change both sprockets and the chain at the same time anyway. Keeps it simple.
Drive chains befuddle me. I've ridden a BMW for 45 years. I am in the process of buying a 1972 Type 94 Wombat 125, and it has a "rare" #423 chain and sprockets, all new. Uses a 6-bolt cush hub. I'm buying the bike to ride, but the packrat in me says to squirrel away all those "period correct" pieces since they may not be available later on.
I _think_ the suggestions that I've read is that the #420, 423 and 428 chains vary in width and not pitch, and the #428 chain will fit the other/earlier sprockets. The Strictly Hodaka Schematics for that Wombat list a #420 front sprocket, a #423 rear sprocket and a #428 chain. And the chain/sprocket bundle seems to suggest #428. Ergo, my befuddlement.
I'm inclined to get a #428 chain for daily use, put the #423 chain up for "show use" and worry about the drive sprockets later. I'm open to being educated.
--Bill
Last edited by Bill2001 on Sat Mar 19, 2016 1:00 am, edited 1 time in total.
Bill,
How often do you plan to ride the Wombat? I have two model 94 Wombats and one still has the original 423 setup. It does get ridden occasionally, including Bad Rock at Hodaka days several times. The other Wombat has all new 428 sprockets and chain. If you plan to ride your Wombat daily, I would suggest a new set of sprockets and chain. If riding occasionally, you could just stick with the 423. What I would not do is put a new chain on an old sprocket set for any extended use. It will just shorten the life of the chain and the sprockets.
Dale
A few things to consider about chain. Sprockets and chain generally should be replaced as a set. A worn chain can cause damage to a new sprocket and a worn sprocket can damage or at least cause premature wear on a new chain. The countershaft sprocket roughly turns and wears about three times faster than the rear. Alloy rears wear faster than steel which somewhat evens things out. There's nothing valuable about 423 chain and I'd just use it up. I guess the bottom line is to inspect all components regularly and maybe replacing the front sprocket if needed during the normal life of the components.
Good opinion, Max. Similar to my "picked up along the way over the years" thoughts. I'll just wear out the new chains that come with the bike and then consider options in a few years.
Dale-- missed seeing your reply yesterday. As I understand it, the bike has new sprockets and chain, of the period-correct #423 size-- it was built as an accurate restoration with attention to detail. I plan on driving the heck out of it, as the phrase goes. When the chain/sprockets on it wear out, I'll replace them with whatever parts bundle Paul/SH offers for the bike.
It sounds like you made a really good find. Have fun with that thing. And don't let it get too close to other Hodaka bikes unless you want more of them. They do tend to multiply...