3 shoe clutch issues

I didn't believe it either until I did the math, you really do need a sprocket this big.

Before I was cruising at 60 and it still had a lot more gear in it, but it was an embarrassing dog at every stop sign.
 
I ran a 52 tooth rear sprocket with a 17hp h2o cooled 68cc Morini with 24" tires and revs up to 15k+ rpms and my top speed is around 50mph. The thing I hated about the 3 shoe was it was very inconsistant. After a few laps, the clutch would engage earlier. If you could get it to engage around 8,200-8,400 rpms, you could be fine but on the track if it engages too soon, you're going to get passes. If you're racing in June, bring a few smaller sprockets.
 
Well I haven't tached it out yet and got my speedometer wound around once, but I'm sure my calculations for a maximum speed of 60mph with a redline of 13500 on 22" tires will be great for what this is, a lead anchor of a cruiser bike with a heavy motor on it, lol.

My whole sense of speed is kinda warped, but I know I've gone 45 on it, my brain doesn't get excited til 60.

I really don't plan on racing this bike, it's too nice, I want to enjoy it every day.
 
I was thinking about what the bike might ride like with a Tomar and a 60ish sprocket, with a single gear I think it would bog the motor if the clutch came on strong at midrange revs, I could be wrong though. Mine's acting like a CVT kinda right now with it slipping, if the clutch starts changing it's characteristics I'll at least change the oil and see what it's wearing like.

This motor with gears would be great, I'm excited about Wild Bill's MTB build using a jackshaft to eliminate the need for a huge jump in gear eduction directly to the rear wheel.
 
16v4nrbrgr said:
Well I haven't tached it out yet and got my speedometer wound around once, but I'm sure my calculations for a maximum speed of 60mph with a redline of 13500 on 22" tires will be great for what this is, a lead anchor of a cruiser bike with a heavy motor on it, lol.

My whole sense of speed is kinda warped, but I know I've gone 45 on it, my brain doesn't get excited til 60.

I really don't plan on racing this bike, it's too nice, I want to enjoy it every day.
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10,500 to 11,000 is a more realistic redline . anything after that the motor lays over and quits pulling . I think with all the noise these motors make it warps your seance of speed a little . I have gps mine at 43 down a short street with a little lower gearing then i have now . But like i said you wont know the true speed until you GPS it .
 
I just realized today I was only pulling half throttle, lol.

I think if you plan on going 60 regularly on a hardtail bike frame you're certifiably nuts, lol.

The thing is, if it's hooked up 1:1 and not slipping at top speed and it's a low drag bike, it will pull toward the redline, mine gets this howl going and goes Bwooooooooo and really picks up the faster you go.

This is my cruiser, I might race it but it's unlikely since I plan to use it to get around Marin County.

I'm working on a tight little cag motobike for racing possibly, I just get a kick out of bringing the town out of the woodwork into the streets and having a leisurely ride with this thing! The gearing so far has been perfecto!
 
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Isn't that the truth! Dudes dig us and women look at us like they stepped in dog poop. That's why I'm going electric for now.
What motor are you running? That bike sounds like a rocket!
 
The clone, it "sounds" like a rocket through a megaphone lol.

I prefer my electric pit bike actually, same HP ir KW-ish and it has mor torque and is quiet, and only a fat sheriff bugged me about it.

I think shifting gears would be great but reliability is the #1 concern for me. The bike is feelin pretty good and the brakes are sufficient, I like the reassurance of one cable brake too.
 
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I don't like riding my clone on the street it's way to loud. I was pulled over once so far on it but the cop was cool.
 
Okay I went for another ride today and emptied a whole happy time tank.

My impressions are that from a stop it usually needs 2-3 lifts off the throttle and then it hooks up toward its final shot toward top speed. It's totally mellow and controllable and will do hill starts and I took it up near top speed with the engine bellowing and the clutch hooked up 100% and it was wild, almost scary, lol.

I think a nice thing about before when I had a 44t on it and it was way overdriven, I could lift off at a cruising speed and the clutch would disengage completely so I could idle instead of now, it stays flung out so I gotta hold throttle in it to keep it from leaning out or slowing down. This is definitely the racing gearing, like on a dirtbike, so it rides like one. If you have a bike that pedals well, having it overdriven would be the way to go for powered cruising above 20 mph. There are so many hills around here, and I should really slow down so I'm gonna try and get used to this, and as the motor breaks in hopefully it mellows out.

I gotta check the clutch and see what the wear is like and change the oil and omit the friction modifier to see if the engagement will lower a smidge to where I want it around 9000. Right now it picks up around 10000.
 
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There's another thing to note, I saw that there's two types of stones for these and the ones you want are the red stone pads with the diagonal oil slots, not the one with a knobbie tire looking pattern, those had issues.

My Martin & Slater I bought about a year ago to this date has the red pads, which seem to work well enough. I'll know how they're wearing after i take a look inside the case next opportunity. It's gonna be a while, but I have to say that for a regular old motorized bicycle that you're not racing or whatever, this clutch works well enough, and it's cheap to replace. If the wear and the spring temper of the clutch work out well long term, I'm not going to upgrade to a Tomar or 2012+ KTM clutch, $$$$ is a four letter word to me nowadays!
 
I'm happy with the Beleville washer setup and I'm gonna wait until it stops acting the way I want it to change to the coil puck springs. 110 miles so far of hard ripping uphill and downhill with some straightaways cruising.

I currently have about ~225cc-ish of Redline D4 in there, clutch picks up at about 9000.
 
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So far so good, although I developed a misfire from it loading up with crap (too rich) and could barely get to the powerband where the clutch picks up, that can be an issue if you ever need to limp it home, don't do like me and put your morini on a bike with good ergo and long crank arms, in case you end up hoofing it home lol. I was able to get it home by clearing it out a bunch with throttle, but today I'll be reducing the back pressure and screwing with the mixture settings. Once it runs better, I'll know how fast it can really go, my muffler has been slowly packing up and the bike has been losing power because of this, today should be interesting!
 
exhaust packing up? what kind of muffler/silencer you using? too much back pressure will melt the piston. even small dia. stingers with no muff melt pistons. a fine line to walk their.
 
It's fine.

Stainless pot scubbers in a gutted long poo.

My bones ache so I'm not riding today, its cold out too. Tomorrow I'll see how much better it is with less backpressure.
 
I always like the tunability of a glasspack silencer. Bigger holes in the inner pipe, less noise.
Flow is tunable with tube diameter, bigger holes don't affect flow much yet really quiet things down.
Pocketbike pipes are a great source of good little silencers. Check out the junk pile at your local china scooter store...
I usually get complete pipes for under $20 bucks.
 
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