I installed mine tonite after work. Took about 30-40 mins including the time it took to remove my left grip to swap my brake lever over to the other side. Now...my thoughts. The USPS box didn't fare so well but the contents were fine. The side of the box split open. The clutch looks good. Mine had a tooling mark on the outer diameter that was probably made by an end mill/program error. I noticed it when I was looking everything over but once on the bike, I doubt anyone else will. I have a GC190 engine on mine and had to use all the shims to shim the clutch per the instructional video. Would be nice to have another shim or two. Allen wrench clearance is tight. A box of 100 Allen wrenches from a supply company would be about $6 for that size. How about including a shortened one with the kit? Even though my tools have a lifetime warranty, I didn't want to go about that tonite. I like the cable that is included. Seems to be the perfect length and operates smoothly. I like that it has a bicycle sized barrel with an adapter that makes it dirt bike barrel sized. Dual purpose. I didn't install the included lever. It looked typical of a Chinese copy. I assemble Chinese Side x Sides on the side and sometimes Chinese quality is lacking. Depends on what expectation you set for them. I put on a used locking rear brake lever off of a Chinese four wheeler that needed a new brake light switch (they don't sell the switch separately so I had to order a new lever). Looks just like the Yamaha Bear Tracker lever that I posted a few days ago. Allows me to disengage the clutch for starting or idling.
I installed this on a DB30 with a Honda GC190 (supposedly 6.2 hp), 70t rear sprocket, 145/70-6 tires. I never rode a stock Doodle Bug. Since putting this bike together a few months ago, it has quickly became my favorite. 12/70 gearing with a stock Max-Torque clutch did fine around my yard. I turned the rpms up to 4000 rpm by adjusting the governor. Otherwise, its stock. With the Downs Bros clutch I need more gear. I actually anticipated this as when a centrifugal clutch slips, you are actually adding in another gear multiplication into the formula. Will probably get a PMR jackshaft. It just lugs too much when the centrifugal would have just slipped thru that rpm range. Its not a problem with the clutch, its my gearing.
My only complaint would be that while I was installing the clutch, if I grabbed the clutch lever, the clutch wouldn't spring back to the engaged position. I cycled the clutch about 20 times and it went away. It hasn't done it since. The clutch now has about an hour of run time on it.
I installed this on a DB30 with a Honda GC190 (supposedly 6.2 hp), 70t rear sprocket, 145/70-6 tires. I never rode a stock Doodle Bug. Since putting this bike together a few months ago, it has quickly became my favorite. 12/70 gearing with a stock Max-Torque clutch did fine around my yard. I turned the rpms up to 4000 rpm by adjusting the governor. Otherwise, its stock. With the Downs Bros clutch I need more gear. I actually anticipated this as when a centrifugal clutch slips, you are actually adding in another gear multiplication into the formula. Will probably get a PMR jackshaft. It just lugs too much when the centrifugal would have just slipped thru that rpm range. Its not a problem with the clutch, its my gearing.
My only complaint would be that while I was installing the clutch, if I grabbed the clutch lever, the clutch wouldn't spring back to the engaged position. I cycled the clutch about 20 times and it went away. It hasn't done it since. The clutch now has about an hour of run time on it.
Hi rmm727,
We appreciate the thorough and honest review of our product. It looks like you're running a 14" tire with a 70 tooth sprocket (5:1) which is just a little bit taller geared than our current setup (5.4:1). You could definitely benefit from running a jack shaft, which will give you a lot more freedom for gearing. Even going with a slightly larger rear sprocket will help you as well. The clutch is designed to stay fully engaged, and sometimes this is not ideal for 'putting around' at 5mph. Also, if you've never had experience with a standard clutch before, it does take some getting used to and to know when to slip it etc.
As far as the key engagement goes, please check out our data sheet here http://www.downsbrosracing.com/DBRT1DataSheet.pdf. We list the minimum shaft length at 2.125" with a continual diameter of 3/4". If you're within this constraint (>90% of the utility engines are), then you are fine with your current key engagement.
On the next iteration, we are going to wire EDM the bore of the male driver so that a key is not required, and shaft length is no longer a concern.
We understand that getting used to this manual clutch can take some time, but we'd love to hear a follow up from you later after you've had some more experience with the clutch. We've found that using a manual clutch just adds a whole new dimension to riding a mini bike once you get everything dialed in
We appreciate the thorough and honest review of our product. It looks like you're running a 14" tire with a 70 tooth sprocket (5:1) which is just a little bit taller geared than our current setup (5.4:1). You could definitely benefit from running a jack shaft, which will give you a lot more freedom for gearing. Even going with a slightly larger rear sprocket will help you as well. The clutch is designed to stay fully engaged, and sometimes this is not ideal for 'putting around' at 5mph. Also, if you've never had experience with a standard clutch before, it does take some getting used to and to know when to slip it etc.
As far as the key engagement goes, please check out our data sheet here http://www.downsbrosracing.com/DBRT1DataSheet.pdf. We list the minimum shaft length at 2.125" with a continual diameter of 3/4". If you're within this constraint (>90% of the utility engines are), then you are fine with your current key engagement.
On the next iteration, we are going to wire EDM the bore of the male driver so that a key is not required, and shaft length is no longer a concern.
We understand that getting used to this manual clutch can take some time, but we'd love to hear a follow up from you later after you've had some more experience with the clutch. We've found that using a manual clutch just adds a whole new dimension to riding a mini bike once you get everything dialed in
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Is there something wrong with this one??? wrong style, material, construction?
Left Side Clutch Lever for Motorized Bicycle Bike Engine Motor Kit Chopper 80cc | eBay
I posted this on the other thread last night. It's clear that I really need to tune my bike after putting this clutch on.
"Learning Curve" mini bike ride w/ manual clutch - YouTube
Left Side Clutch Lever for Motorized Bicycle Bike Engine Motor Kit Chopper 80cc | eBay
I posted this on the other thread last night. It's clear that I really need to tune my bike after putting this clutch on.
"Learning Curve" mini bike ride w/ manual clutch - YouTube
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WOW, what a huge difference...
I swapped out my 60t rear sprocket for the original 75t that came on the Motovox,
then turned the idle up 1/2 turn (dif between a low rumble and running engine ready to rev),
then tuned the idle with the little idle adjustment screw/jet (the one that doesn't do much),
it's a ruxing carb. Holy Hallelujah; there is no lug at all, smooooth take-offs, easy to ride,
pop the clutch fast starts, wheelie's are breazy, I did my first smokin burn-out, AND I bump started it too....
Ok, so I didn't jump on it till after it started, but it was a good push bump start. Hahaha!!!
I couldn't be happier! If you have a few things that need changing to get this to work for you,
change 'em. After I calm down I'm gonna make another vid....:innocent:thank you
and here it is...
http://www.youtube.com/watch?v=i9ktC7IKjrU&feature=player_embedded
I swapped out my 60t rear sprocket for the original 75t that came on the Motovox,
then turned the idle up 1/2 turn (dif between a low rumble and running engine ready to rev),
then tuned the idle with the little idle adjustment screw/jet (the one that doesn't do much),
it's a ruxing carb. Holy Hallelujah; there is no lug at all, smooooth take-offs, easy to ride,
pop the clutch fast starts, wheelie's are breazy, I did my first smokin burn-out, AND I bump started it too....
Ok, so I didn't jump on it till after it started, but it was a good push bump start. Hahaha!!!
I couldn't be happier! If you have a few things that need changing to get this to work for you,
change 'em. After I calm down I'm gonna make another vid....:innocent:thank you
and here it is...
http://www.youtube.com/watch?v=i9ktC7IKjrU&feature=player_embedded
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Without putting my hands on one, I really can't be sure, but I'm not a fan of using the bolt like that. It sounds like what you need is a hat. Basically a real thick washer with a shoulder on it. You would have 5/8" OD up to the shoulder. Then bigger after that. This way the bolt could be torqued down and not be putting pressure on the clutch. You could include a hand full of 5/8" shims for "tuning" the length if need be.
Like this, but not so long...
Like this, but not so long...