Buying my first 4 stroke

FNTPuck

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Jul 2, 2018
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Seems this has a 1 piece crank. Are all cranks the same size or do I need to measure this as well? Also, if I extend my pedals out more, wont that mess with the original bike chain alignment?
Wide cranksets don't move the crank, just a longer arm through the bottom bracket. Crank is same spot, pedals are farther apart.
 


pwd847

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Apr 21, 2019
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OD of hub is 39.07 mm. Online says that converts to 1.538in. Not sure how to proceed with this weird number. Should I just buy a 1.5" adapter? Bike shop told me that.
 

FNTPuck

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879
OD of hub is 39.07 mm. Online says that converts to 1.538in. Not sure how to proceed with this weird number. Should I just buy a 1.5" adapter? Bike shop told me that.
Yep, youre lucky. Some of the cheaper hubs are slightly smaller instead of slightly larger, so in that case you need to mill down the ends of the adapter to fit properly or else the ends will touch before its firmly against the hub.

With those numbers you will be good to go with a 1.5" adapter.
 

pwd847

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Apr 21, 2019
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Any suggestions on where to get a decent hub adapter and sprocket? I've seen some for about $80, but I hope that's on the high end.
Also grabbed some high temp "make your own gasket" rtv. I remember the gaskets on my 2 stroke were junk.
 
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pwd847

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This is pretty much the only > 44T sprocket I can find. Is this really worth $75? Why aluminum instead of steel?

https://www.ebay.com/itm/1-5-Hub-415-Chain-CNC-48T-Sprocket-With-Adapter-49cc-80cc-Motorized-Bicycle-/283000640303&ved=2ahUKEwjL24O9ge7hAhVCQ6wKHSOFAKEQjjgwAHoECAcQAg&usg=AOvVaw0yr6yk5a2iaot8leqVzZXE[/URL]
Actually I just found this. I'll probably get that.
 
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JerboaJohn

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oh you don't have to shop gasbike. plenty of other suppliers, better even,, gasbike(aka nationwideaccessories on ebay) has a some bad reviews.
have a look @ https://mbrebel.com/motor-parts/
I know they have 58, 62 and even a 68T. but yeah the package with adapter + sprocket will run about that much. good CNC aluminum sprockets run about $45+. the adapter is cheaper.
stock sprockets wont fit the 3 bolt adapters. some sprockets are what they call 3-6-9 so they fit all the mounting designs.
there are some stamped steel sprockets bigger than 44T. 56T is the most common. Aluminum saves you weight but still can handle some good torque

hope this helps
 

pwd847

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Apr 21, 2019
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What size pedal axle should I get? I found this video : https://www.google.com/url?sa=t&source=web&rct=j&url=#&ved=2ahUKEwij46vI4vLhAhUIQ6wKHTiVBpMQwqsBMAN6BAgHEBU&usg=AOvVaw0VTJzWxrN8ZFOD4xbU2nov

It seems like he just uses a regular conversion axle and the provided crank arms. So I may not need the extra wide ones?

Edit: I guess when I say "size" I mean the length. The hole seems to be the normal beach cruiser 2" size.

This is the last piece I need before this job is ready to assemble. I'm really excited!
 
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Will'smotobikes19

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Apr 9, 2018
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The MBrebel size with the green bearings. The chineseum wide crank sucks and the sprocket isn't straight the threads strip and nuts fall off because the square ends don't seat right on the shaft.
 

pwd847

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Apr 21, 2019
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The MBrebel size with the green bearings. The chineseum wide crank sucks and the sprocket isn't straight the threads strip and nuts fall off because the square ends don't seat right on the shaft.
While I do want a quality build I just can't bring myself to spend another $140 just to have a place to rest my feet.

What about this: https://www.gasbike.net/collections/chains-sprockets/products/wide-pedal-crank-kit-2pc

Or this: https://www.kingsmotorbikes.com/products/wide-pedal-crank-kit-2pc

Actually they both look like the same thing.

Here is one on Amazon : https://www.amazon.com/Assembly-Stroke-Bicycle-Replacement-Motorized/dp/B00KWLL8K8/ref=sxbs_sxwds-stvp?keywords=80cc+crank&pd_rd_i=B00KWLL8K8&pd_rd_r=b49609e0-9917-44fa-8298-85b24ff3402e&pd_rd_w=HZv2U&pd_rd_wg=Oc3NB&pf_rd_p=a6d018ad-f20b-46c9-8920-433972c7d9b7&pf_rd_r=YD1DNT2PC16DZQGYWZNP&qid=1556462505&s=gateway

However on my next build in a couple years that is something that I may invest in.
 
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