The Hodaka Club Forum

Thanks guys I’m having fun with this but if it doesn’t rip it’s all for nothing .
Another mile stone
Air leak test passed.

Getting close now , I’m just waiting on my pipe .

Ooh- I'm loving the progress, Third. I have a quick question. From what I recall, the maximum allowable fore/aft inclination for the Mik is 20 degrees before you start to impede maintenance of proper fuel level in the float bowl. My spectacularly inaccurate eyeball compass puts yours at 30ish. Here's what I know. Your bike is going to drink like a fish. Now the question - are you concerned about maintaining proper fuel height in the float bowl at that angle to feed the motor? I know there is the possibility of tweeking the float tab to allow maintaining a more appropriate fuel availability, but that sounds a bit fiddly to me. I would question whether an angled shim used to trim out some of the carby angulation might interfere with the flow dynamics of the intake track on a motor that is really going to gulp. I'd be really interested in hearing your thoughts on this matter when you get minute. Great work!!!

A mixed "serious and semi-serious" set of comments follows . . .

1. I've seen some equally steep (by visual guesstimation) carb installations which seemed to work out fine, so testing as is would seem appropriate.
2. This machine is going to spend a large amount of its time on the track waving the front wheel in the air (which reduces the "steepness" of the carb angle) . . .

. . . waiting to hear how it goes.
Ed

Haha you are both right. Matt , correct 20 deg is what Mikuni say is the max angle, this is right on it. I ran another case reed engine at this angle and it wasnt a problem . When an MX bike is mobile it’s rearly upright anyway. I have done some mods in the carb to help though. The main jet drinks from the bowl nut. There is a disc thing that the main jet sits in ,this is a baffle. it’s job is to ensure that the main jet didn’t get uncovered.fuel gets into the nut from around it( it’s not a seal ) and through two tiny holes in the disc. I drilled couple of more holes in it to make sure the nut gets filled quicker, I didn’t know what affect the extreme angle would make on the nuts supply. You can buy deep nuts as well and I looked at that but they wouldn’t fit with the clearance I have. I have toyed with the idea of a pumper carby, I even bought one . I couldn’t work out how it worked and as the Mikuni was working I didn’t pursue it any further.

This is the first case reed engine I made . The reason I made another is that this one has a bolted on reed block and is a pain to fit. The other main reason is that during making it I put the cases through Hell in the BBQ and under gas torch , it took me 3 attempts of production. First JB Weld (it leaked air ) then aluminium rod welding ( nightmare) then TIG. The cases warped so I had to machine them flat which meant I had to use a gasket between the cases to stop pinching the crank. After all that it went really well. It has a ported stock sleeve. I wanted to make another one without those problems plus try to improve the porting .

A close up , pre airbox .

Thanks Third. I was wondering if the angle of the bike in the photo enhanced the appearance of the angle. As The Captain suggested, one of my riding buddies races show machines and on his main sled, he runs Mikunis set in at just under 30 degrees to horizontal without issue. The thought is that the agitation and terrain variation keeps bowl level adequate. I'm really digging this build. Thanks again for sharing it with us!

Now it’s running , just idling to check things out . Baby steps.

I couldn’t work out how to post videos so here is a YouTube clip.

https://youtu.be/9a7VZn2ugH4

Hell's bells. I'm never able to get these video links to play on my set up. What is the title of the video, if you please.

Error

https://youtu.be/9a7VZn2ugH4

Try that or search Case Reed Hodaka 125[/quote]

Video played on my computer just fine. Kev, that's an amazing amount of fabrication you've done on that engine! I think I've had almost as much fun following this post as you have had building that engine! Can't wait to see the final results.

Thanks Third! Sounds great. What a build!!

Good news for me , I’m done with the assembly. I just have some little bit to do on the tanks and make sure the clutch is adjusted.

Not bad for a bike made from spare parts .

Engine close up

Amazing, Third. Just amazing. I dig how you combined the Super Man shield with the Hodaka logo. Contrary to the carburetor suggestion, this bike is going to fly. "Not for aircraft use". Ha!! What are you going to start with in the secondary/drive sprocket department?

Matt it’s 14 64 or 62 . I can’t see the number . It’s all I have anyway.

I’ve got a problem now with the clutch. Just checking it out today post assembly. The clutch drags when it’s pulled in . If I don’t raise the revs and hold the brake it will stall. I’ve gone back to stock clutch and adjusted the hell out of it but no use. I started with1/4 freeplay at the case lever which normally works. I’m thinking he clutch I fitted was assembled a year ago and by now the plates are dry. It does move in and out in the vice.

Any ideas?

I'm sure this has occurred to you, but in times like these, I start from scratch. Pull the clutch, completely dismantle it, and inspect all of the components. That the springs compress doesn't mean you don't have a plate or three frozen together. Also, if not done at the time, its really good policy to blue print the clutch. You might have a heavily grooved cage that is hanging up the steels. Also, make sure the pinion bushing is not mushroomed and that the assembly order of all components is correct and that all components related to clutch function are within spec. Are there any unusual sounds occurring when you disengage the clutch? I'm sure all this has occurred to you, but by running through this check list I have yet to encounter a clutch issue I can't sort out.

Matt
I basically did what you said , full strip down and inspection. No missing parts. The one thing I did see was grooving on the basket.
I filed that out and went over the blueprinting .
Reassembled and set the lever arm to 3/32 .
Now it works perfect.

Sweet!! I'm glad you're in business. Its really a great clutch design. Kinda fun to work on, too. I'd be interested in where you rest on the great clutch assembly debate. Wire or Ny-loc nuts? I'd love to see some video of you dialing in the bike when you get it on the track!!

I’m not really for one or the other . I use very light weight aviation pressed steel locknuts, mainly because all my clutch bits have damaged threads. Let’s just say they are locally available. I just drill them out and fit a screw and nut.
Nylocks are a bit taller and heavier , I try and keep the clutch assembly as light as possible. Nylocks could also hit the clutch case boss, you would know first kick if that was a problem.

Yep, as stout as these clutches are, that threaded aluminum alloy is an Achilles heel I've seen on a couple of my bikes from someone (me) going Ape$4it with the driver during assembly. Hey - at least they didn't work their way out. Those clutches can be all but destroyed. Wired.

A quick run up of the engine from this weekend.

https://youtu.be/tNOJbyQ93Vg

Sounds AWESOME!! Superb build, Third. I've had such great enjoyment watching this bike come together. I can't wait to see it on the track.