Mantini MBK 1

zefer

Zefer t Motorsport
#82
Well Mr.Wizard i will take that as a compliment and I will continue to keep up with the progress.this is a cool build and im having fun doing it... I have to be careful with engineering the tank and battery box as it came to me powder coated...so no welding
Everything needed to complete this will need to be "bolt on"
Or brackets but we shall prevail
As its not such a bad problem to have I will have
More when i start fitting up the chains and drive line.. and cutting down the shaft and centering the engine and and and
 

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Minimichael

Well-Known Member
#83
I'll bet a 390cc would fit that frame nicely. Might give your suspension a proper work out too. I've been wondering: Does the short shock equate to a stiffer ride? I noticed the old Powell in another post showed a similar (albeit prehistoric) design.
 

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zefer

Zefer t Motorsport
#86
Fenders....not this bike...motor...
Though its tiny in comparison
The little 212 has a ton of
"Hot sauce" if ya know what i mean..i will post the motor build later...this little Tilly dynoed @ 18 HP...we shall see. I tell you what
There is a good deal of resistance turning the rear wheel
I attribute that to the extra 2 gears and jack shaft...and it being brand new chains. The point is thats a power robbing drive line... I will work it out after shaking it down. I think I am going to mount the battery on the engine top plate...annnnd
Still working out the tank...oh yeah and I "modified " the kick stand for a better lean angle
Enjoy the pics....it's starting to look like a real mini bike
 

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zefer

Zefer t Motorsport
#89
I'm pretty sure i still am having clearance issues with my rear wheel...so here goes ...the rear wheel...complete with the brake disc Quick change hub and a split 72 tooth rear sprocket... I feel like when tightening the rear wheel axle the wheel gets tight too tight if i back off the nut it frees up....and once the drag of all the gears and chain along with the caliper is accounted for its really difficult to push
It seems logical to strip the chain
Pull the wheel and remove the sprocket and rotor and just mount the bare wheel to get a ifea of what happens when the axle is torqued properly...one we get this sorted start adding one thing back at a time and repeat the process until I introduce the drag back into it... you guys have any thoughts ? I am suspicious of the axle spacers...with no facts to back it up..just a gut feeling...mmmm whats up with this
 

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Minimichael

Well-Known Member
#90
I'd be guessing the same, unless your external axle spacers are somehow creating drag on the outside bearing seals? Maybe you could test the wheel off the bike by tightening a bolt between just the bearing outsides. Of course before that you'll have looked to assess that inner spacer. Could it just be real stiff grease inside the bearings? Or might it be a bearing that's not fully seated yet?
 
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zefer

Zefer t Motorsport
#93
Sam has been great at supporting me in this and I think a fresh perspective from you guys will give me a direction to go in
We are snowed in here so no work...no mini bike as its at the shop and im not moving right now
 
#94
I would think if you just loosen the axle nuts and the drag goes awaybyou have then isolated the problem. Misalignment in the rear wheel like toe-, toe-out can cause drag also. Your methodology is good. When tshooting, isolation of components, one at a time is the best practice.
 

Thepaetsguy

Well-Known Member
#95
Inside your wheel, between the bearings, is there a tube spacer on the axle? With a spacer, you can tighten the axle. Without the spacer, tightening the axle nut will put the bearings in a bind.
Exactly there should be a sticky about this the spacers are at T@S in standard and heavy duty.

Of course you know this but just saying for anyone who doesn‘t do not just tighten it till it locks the wheel up then back it off...

I’ve seen the axle wear out the bearings that didn’t have a spacer. It locks up and either spins the nut off or spins the axle inside the frame.
 

Thepaetsguy

Well-Known Member
#99
I’m blown away it’s not a factory live axle with a split quick change. Is the rear expected to hold it’s ride height in that notch with just the nuts tightened?? I’m not bashing the bike is American and looks fantastic.

Just don’t like that rear axle setup..
 

zefer

Zefer t Motorsport
Seems to be fine for now... I will shake it down pretty good before calling it a day. I have decided to go with this tank for now and I think i will make a top plate that runs from the seat to where the frame rises to meet the steering neck....this can support a nice barrel tank or a number of other options and perhaps switches for lights. I like the black tank. I think it's clean and simple. I have to work out a battery box for the E-start and lights...yall have looked at alot of photos...any suggestions or ideas
 

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