need clutch advice for mmb80 Predator upgrade
Hey slash pine, welcome to OldMiniBikes. TAV is for Torque-A-Verter, that was Comet's brand name for their 30 series Torque Converters. Sometimes called a TAV2. Sounds like you will want a TAV if you have significant hills, and you should also be able to reach some interesting top speeds with a TAV, won't necessarily short you on top speed. If you're using a clone motor you may have to make some mods to the TAV and/or your frame to fit. I'll let the gear heads chime in with the optimum tooth n sprocket numbers but you can search the site in the meantime, tons on the subject. Good luck!:thumbsup:
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On one of my minibikes I use a PMR bolt on jackshaft partly to approximate the effect of a TAV, I use it with a Max-Torque Box Stock/Clone clutch (modified with optional heavier wedge type shoes). On my other bike I use just a straight 11t clutch to 60t rear sprocket and happiness abounds both minibikes, different rides n feel; both baddass!:thumbsup:
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I run a 11 tooth clutch. Stock in for rear teeth. I'm 6'2" 200lbs. The bike will wheelie on my from take off, if I floor it.
In order to install a 212cc on that bike, you're going to have to do the following;
Grind down the front oil drain plug flat with the engine case, and slide the engine all the way forward to mount it.
You're also going to need to order a longer chain. Stock one is like 10 links (+/-) a few links. So, order a chain braker while you're at it.
Now... you won't be able to use the stock chain cover. So you will need to come up with something for that.
Me and someoneelse on here is/are doing the same conversion.
If you have any more questions, just ask.
Hope this helps, Lyle
In order to install a 212cc on that bike, you're going to have to do the following;
Grind down the front oil drain plug flat with the engine case, and slide the engine all the way forward to mount it.
You're also going to need to order a longer chain. Stock one is like 10 links (+/-) a few links. So, order a chain braker while you're at it.
Now... you won't be able to use the stock chain cover. So you will need to come up with something for that.
Me and someoneelse on here is/are doing the same conversion.
If you have any more questions, just ask.
Hope this helps, Lyle
You can find some pictures of my bike i'm building here: http://www.oldminibikes.com/forum/general-minibike-talk/103919-what-is-everyone-working-on-3.html
I'm thinking that just the 212 upgrade (from 80cc) is going to have enough torque to pull up the hills...time will tell...but I really want to make the most logical choice in the number of clutch teeth...I hate to buy a second or even a third clutch if I get the best one for this bike (MMB80)/upgrade from the onset...Thus my query here...
In the thread 'ShapeShifter' started about his upgrade of the same model bike...although he used a TC...he advised: ...so am a bit confused...would a 12 or 13 tooth clutch not be so quick to bring the front end up?
If I start off with a 12T clutch and it works but not as well (or too well) as I like I should be able to tell which direction I need to go, 11T or 13T from there...or realize I need a TC... So now unless someone steers me differently I'm leaning towards a 12T clutch...hope to order one tomorrow from OldMiniBikes Warehouse (How are they for shipping?)
Will a die grinder or Dremel tool not suffice for cutting a new chain to length?
Looking at the pictures in ShapeShifter's thread...it appears there may (or may not) be enough room height wise to use a slightly raised adapter plate??...possibly enough eliminate or reduce the cuts/grind on the Predator...once I have the 212 on hand I will know for sure...??
In the thread 'ShapeShifter' started about his upgrade of the same model bike...although he used a TC...he advised: ...so am a bit confused...would a 12 or 13 tooth clutch not be so quick to bring the front end up?
If I start off with a 12T clutch and it works but not as well (or too well) as I like I should be able to tell which direction I need to go, 11T or 13T from there...or realize I need a TC... So now unless someone steers me differently I'm leaning towards a 12T clutch...hope to order one tomorrow from OldMiniBikes Warehouse (How are they for shipping?)
Will a die grinder or Dremel tool not suffice for cutting a new chain to length?
Looking at the pictures in ShapeShifter's thread...it appears there may (or may not) be enough room height wise to use a slightly raised adapter plate??...possibly enough eliminate or reduce the cuts/grind on the Predator...once I have the 212 on hand I will know for sure...??
slash, I hope others chime in with their opinions. Using a clutch with the 212 will be fine. You will not notice much difference in 11,12, or 13t sockets, but 11t will climb the best, but you will just have to get used to managing your throttle twisting. A clutch can be grabby, and it can also get hot on lots of hills, but it will definitely pull you up them. I prefer the torque converter because it delivers power smoothly and they are load sensing - i.e not "grabby".
A clutch-on-a-hill scenario:
Lets say your on a steep bumpy hill (not a typical suburban street), you are slowly making your way up but the slipping action of the clutch isn't moving you over some bumps (and is probably getting hot), so you carefully twist until you get the power you need. However, this little bit of power may come as a jerk with a clutch and if the hill is steep enough, may flip you off the back. With the TC, none of this is relevant - it just goes uphill while you sip a cocktail and/or cut diamonds.
As far as room for an adapter plate, you wont have room for the stock muffler, but some aftermarket mufflers will work.
A clutch-on-a-hill scenario:
Lets say your on a steep bumpy hill (not a typical suburban street), you are slowly making your way up but the slipping action of the clutch isn't moving you over some bumps (and is probably getting hot), so you carefully twist until you get the power you need. However, this little bit of power may come as a jerk with a clutch and if the hill is steep enough, may flip you off the back. With the TC, none of this is relevant - it just goes uphill while you sip a cocktail and/or cut diamonds.
As far as room for an adapter plate, you wont have room for the stock muffler, but some aftermarket mufflers will work.
Thanks for the further insights...I truly appreciate the replies... I would love to hear other sage advice on the clutch teeth...My real concern is what will work best without having to mess with the OEM 75T rear sprocket...before seeing what just a 11,12 or 13 tooth clutch and the 212 upgrade will do...
I'm mostly a tractor guy so I'm familiar with what we call the "pucker factor"
hmy: Which I'm sure can occur with an unexpected/surprise dumping...!!
My background with tractors and counter weights etc...has me thinking I can possibly add some weight to the front fork/wheel...and possibly a larger front wheel/tire that could be filled with ballast (like beet juice or 'Rim Guard' etc.)...I know even a larger tire won't hold that much ballast but it could help some and it is the only way to add weight to the front and help a bit keeping the c.o.g. lower...
I've also read all the threads/posts I could find on "sidecars"...Not specifically to carry another person but some type of cargo container that could possibly solve a wheelie issue...? and give me some payload space...
Not trying to toot my own horn but my design/fabrication skills and resources allow me to do just about anything at this level...so I don't see upgrading to a TC/TAV a big deal if need be...and after all the reading I've been doing here on OldMiniBikes I find myself looking down the road and a second bike build...time is a commodity around here but I am becoming quite intrigued...
Thanks again for the replys/answers...
I'm mostly a tractor guy so I'm familiar with what we call the "pucker factor"
hmy: Which I'm sure can occur with an unexpected/surprise dumping...!!My background with tractors and counter weights etc...has me thinking I can possibly add some weight to the front fork/wheel...and possibly a larger front wheel/tire that could be filled with ballast (like beet juice or 'Rim Guard' etc.)...I know even a larger tire won't hold that much ballast but it could help some and it is the only way to add weight to the front and help a bit keeping the c.o.g. lower...
I've also read all the threads/posts I could find on "sidecars"...Not specifically to carry another person but some type of cargo container that could possibly solve a wheelie issue...? and give me some payload space...
Not trying to toot my own horn but my design/fabrication skills and resources allow me to do just about anything at this level...so I don't see upgrading to a TC/TAV a big deal if need be...and after all the reading I've been doing here on OldMiniBikes I find myself looking down the road and a second bike build...time is a commodity around here but I am becoming quite intrigued...
Thanks again for the replys/answers...
Weighted front wheel is not necessary. Just a learned control of the throttle twist, like any overpowered motorcycle.
If you ever decide to go the TC route, let me know and I can talk you through how I did it. Me and another guy called Carlo.c over on this forum that did the same thing, I came up with the solution, but he is a better fabricator than me (even though I just beat him for the Classic Mini of the Year contest :wink.
If you ever decide to go the TC route, let me know and I can talk you through how I did it. Me and another guy called Carlo.c over on this forum that did the same thing, I came up with the solution, but he is a better fabricator than me (even though I just beat him for the Classic Mini of the Year contest :wink
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