clutch tuning question
- Thread starter greaser_monkey
- Start date
- Tags clutch question tuning
My engine is not on a mini, it's on a bicycle. It will cruise above 30 mph, and my desire is not to go faster but to climb hills better. The engine does not take up the whole space of the frame, but no matter what angle I try to put the motor mount at, I always run into carb clearance issues with the seat tube. Hence stangr's custom intake. It will allow me to mount a carb away from the frame. I do believe that a properly tuned carb will get me just north of 6k, and this will allow me to change my gearing from 12.44:1 to 13.78:1. I am also planning to eventually switch to a frame with thicker tubing and downsize to 24" wheels. I've got a Yamaha brake drum off a 1975 dirtbike that I'm planning to lace into a 24" wheel for my front wheel. I will be adding a disc brake to my jackshaft hub for an emergency brake (only because the yamaha drum will be more than adequate for normal stopping and others who have done the jackshaft disc brake say they grab extremely hard, probably due to the gearing advantage). So as I've said, I'm shooting for just north of 6k. I like to cruise, not rip. The gearing change will consist of upsizing my rear sprocket from a 44t to a 48t. This should give me better climb as well as smoother takeoff. I'm working with the clutch in the meantime to do what I can. A washer costs like 50 cents, so it's not an expensive modification and if it works it may become permanent. I will service the clutch periodically and inspect the washer for wear. If/when it becomes worn, I can replace it. I understand that once the clutch is fully engaged, it is balanced. But it is not balanced until it is fully locked. Having it pre-balanced may help or it may not. For a 50 cent washer, it's worth a shot.
Dude! Why didn't ya tell us that from the start?
Have ya considered an old chainsaw motor? They are very lightweight, can rev to the moon, and give decent power. There are also lots of old snowblower engines on eBay...the Tecumseh ones are cheap. One of the messages that was maybe misinterpreted was the the little Lifan motor does not have any aftermarket support and is not a great candidate for upgrades. We don't want you throwing good after after a bad idea...that is all.
...and we don't want to see you get hurt...you probably won't believe me now, but are all about a good time here!
Have ya considered an old chainsaw motor? They are very lightweight, can rev to the moon, and give decent power. There are also lots of old snowblower engines on eBay...the Tecumseh ones are cheap. One of the messages that was maybe misinterpreted was the the little Lifan motor does not have any aftermarket support and is not a great candidate for upgrades. We don't want you throwing good after after a bad idea...that is all.
...and we don't want to see you get hurt...you probably won't believe me now, but are all about a good time here!
I tend to take things with a grain of salt, but I also defend my goals and wishes. I'm not mad and not taking anything personally, just trying to get a teensy bit more out of an engine that's been pretty good to me thus far. When you're revving the crap out of a tiny engine with 12" wheels, I get the concern of the flywheel. 6k with bicycle wheels ain't pushing the engine that hard. I didn't say anything about it being a bicycle because I didn't want to get flamed out of the forum. Kinda silly now maybe. I've had this engine for a little while and I'm happy with it except for not having quite as much torque as I would like. A tuned carb should change that by adding enough power to be able to lower the gearing. I was considering a 79cc predator, but I like the look of this engine better and I think it was through a conversation with stangr that it occurred to me to up the power and lower the gearing. Kinda kicked myself for not thinking of it before. But yall have a good night. I gotta hit it.
waste of time and money
this is why you should not modd this engine it is NOT well made this damage was from riding WITH the governor intact :scared:
better shots of the "clone" and the real deal it was "cloned" from
this honda has taken a beating from 3 riders 2 adults and 1 child it wont die real deal honda is where it is at
better shots of the "clone" and the real deal it was "cloned" from
this honda has taken a beating from 3 riders 2 adults and 1 child it wont die real deal honda is where it is at
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I went to home depot and got a fiber washer that is. 062" thick to replace the stock fiber washer that is less than half as thick. This will definitely take up some of the play. I may even use the replacement washer and the stock washer together. All the discussion about other modifications is really off topic. I started this thread asking about clutch tuning/balancing, nothing more. Whatever else I choose to do to my engine/bike is my business.
well if your good at it then you would know that maximum torque peaks at the rated 2500 rpm's. no matter how much rpm you spin it it will not change that. you will need to spend money on things that will increase the torque of your engine. compression and displacement are those things,how much will that cost?
how much torque increase do you think you can make by bolting on something's? 50% gain,100%? even at 100% the most you will get is 7 ft/lbs. the 212cc is 8.1 ft/lbs for $120 bucks reliable HP. again how much are you planning to spend?
how much torque increase do you think you can make by bolting on something's? 50% gain,100%? even at 100% the most you will get is 7 ft/lbs. the 212cc is 8.1 ft/lbs for $120 bucks reliable HP. again how much are you planning to spend?
Well, I fired the bike up in the alley behind my house, hopped on and gave her some gas. Clutch engagement is very smooth so far. I only went a few feet, but there was no chattering at all. I went up the alley, stopped and turned around and putted back towards my house. The clutch was smooth the entire time. In a few minutes I'm leaving to do a speed run and when I get back I'll do a plug chop. Let you all know how everything goes later on.
So here is an update. I replaced the bushing and kept it well lubed, but clutch engagement was not as smooth as I would like sometimes. So I ordered the wedge shoes from comet kart sales. They got here today. I started with all 6 wedge shoes, but the clutch was engaging way too early and chattering badly. So I alternated, every other shoe heavy, every other shoe regular. The clutch engages around 2500 or 2600. This is optimal engagement for pedal assisting (remember, this is on a bicycle). The total weight of the stock shoes is 276 grams. The total weight of my shoes is 324 grams, so it's like the weight of another regular shoe added on basically. The clutch will engage on its own with very minimal slippage, but I accelerate a bit quicker by pedal assisting, and this is good because it should make it easier to pedal assist going up hill when necessary. So there you have it. This clutch works well with some assistance.
I never thought about alternating shoes, good idea, I may try sometime.
I did notice recently that the light shoes, which have less side area, tend to lay over (engage the edge of the shoe), and will wear a groove in the drum. So, I now favor the wedge shoes for that reason. Plus, my engines are making enough torque now so they don't need to slip the clutch as much as a stock engine.
I am slipping my clutches less now.
I did notice recently that the light shoes, which have less side area, tend to lay over (engage the edge of the shoe), and will wear a groove in the drum. So, I now favor the wedge shoes for that reason. Plus, my engines are making enough torque now so they don't need to slip the clutch as much as a stock engine.
I am slipping my clutches less now.