Older Roramaster

vkray

New Member
Jun 26, 2020
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Hey there, folks! Hope I find a few friends here? I want you all to know that I am almost totally new to building a motorized bicycle. I am at a disadvantage starting out, I have very poor vision, like I am legally blind. (it is very hard for me to even write the words, honest!
But to me this is a challenge, and I love changless. I am also a very old man 76 years old.

Having said all of that, I have run into a few problems. #1. Rear drive sprocket, hub. Because I thought it would be easier, I purchased the CNC machine rear hub bracket assy, actually 2, 1" and the 1 1/2", of which is the problem. Neither one fit the hub.
The wheel size is a 700c the hub size is 1" I believe. Not sure do not have calipers!
The one inch adapter is to small to fit the hub.
What wheel do I need to get to fit the adapter?
Thank you!
I can send pictures if requested?
 

vkray

New Member
Jun 26, 2020
12
13
3
76
Hey there, folks! Hope I find a few friends here? I want you all to know that I am almost totally new to building a motorized bicycle. I am at a disadvantage starting out, I have very poor vision, like I am legally blind. (it is very hard for me to even write the words, honest!
But to me this is a challenge, and I love changless. I am also a very old man 76 years old.

Having said all of that, I have run into a few problems. #1. Rear drive sprocket, hub. Because I thought it would be easier, I purchased the CNC machine rear hub bracket assy, actually 2, 1" and the 1 1/2", of which is the problem. Neither one fit the hub.
The wheel size is a 700c the hub size is 1" I believe. Not sure do not have calipers!
The one inch adapter is to small to fit the hub.
What wheel do I need to get to fit the adapter?
Thank you!
I can send pictures if requested?
And the 1 1/2" is to big?
 
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Russell

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Apr 19, 2009
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MA
Its old most likely 70s vintage? Pic of rear wheel
You made me chuckle when you said "older" I am also 76 and older means pre 50's to me! I have built many MB's including a 48 Roadmaster. Never used a hub adapter but also never had a problem with the standard kit sprocket setup. I also have thousands of miles on my builds'
 
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LR Jerry

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Dec 19, 2011
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Rockwood, TN
Could you provide more of a direct view of the side of the wheel? This'll help give a better idea of what you have when looking at the angled views of the wheel hub.
 
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5-7HEAVEN

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Aug 2, 2008
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Hey there, folks! Hope I find a few friends here? I want you all to know that I am almost totally new to building a motorized bicycle. I am at a disadvantage starting out, I have very poor vision, like I am legally blind. (it is very hard for me to even write the words, honest!
But to me this is a challenge, and I love changless. I am also a very old man 76 years old.

Having said all of that, I have run into a few problems. #1. Rear drive sprocket, hub. Because I thought it would be easier, I purchased the CNC machine rear hub bracket assy, actually 2, 1" and the 1 1/2", of which is the problem. Neither one fit the hub.
The wheel size is a 700c the hub size is 1" I believe. Not sure do not have calipers!
The one inch adapter is to small to fit the hub.
What wheel do I need to get to fit the adapter?
Thank you!
I can send pictures if requested?
Welcome vkray. I'll be 74 in December.
Others with this experience will chime in.
 
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indian22

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Dec 31, 2014
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Welcome VK ! 73 here as of this week and vision impaired as well. Slows us down but can't keep us from what we love. I personally start with new wheels on each build and use 1.5" hub/sprocket adapter. Not the cheap route but it has its advantages for my vintage style bikes. The biggest is I buy exactly what I want and not what I'm stuck with the drawback is $$ up front and to many that's a big problem that is perfectly valid.

There are different approaches to each step of a build which makes it a bit more interesting build to build.

Rick C.
 

curtisfox

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Dec 29, 2008
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Welcome! 700's are considered 28" and the best you can get with a bigger hub is 26" i believe, and maybe 2" wide, depends on your frame. And watch the spoke count most adapters and rag hookups are designed for 36 spoke. Rag joints do work good but got to get them right centered, even tightness, no warble. Chain alignment is very important also straight edge, one sprocket to the other. Best would do a search on bike wheels, most bigger hubs are coaster brake. I will be 79 in Oct.


https://www.huskybicycles.com/wheels.html
 
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vkray

New Member
Jun 26, 2020
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Welcome VK ! 73 here as of this week and vision impaired as well. Slows us down but can't keep us from what we love. I personally start with new wheels on each build and use 1.5" hub/sprocket adapter. Not the cheap route but it has its advantages for my vintage style bikes. The biggest is I buy exactly what I want and not what I'm stuck with the drawback is $$ up front and to many that's a big problem that is perfectly valid.

There are different approaches to each step of a build which makes it a bit more interesting build to build.

Rick C.
Thanks for the reply. So what size rear wheel do I get? Any clues
 
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vkray

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Jun 26, 2020
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Thanks for the reply. So what size rear wheel do I get? Any clues
Ok, since I last posted i took the wheel to my local bike shop. He told me the wheel was not good for a motorized drive.
So my next step is to find a rear wheel that will work?
The diameter of the wheel is 29" or 700c, my question is will a 26" wheel work?
Because that is all I am finding, if it does work do I also need to do the same size for the front wheel?
 
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indian22

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Dec 31, 2014
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Vkray you ask what seems such a simple question or two about almost any part or step required for building a motorized bike and find that the answers seem to hinge around '" It depends" lol. So many variables involved due to the wide range of bike brands, styles sizes, materials, brakes and it goes on and on. Bear with us on this. Russel has built on the Roadmaster frame and he is a really good builder so I know these can motorize with a rag joint. I was hoping someone with direct knowledge of the frame you have will join in with a definitive answer for wheel and tire application using a hub adapter & appropriate wheel and tire combination and that would be ideal. In the meantime I'll add a bit to what's been said to this point.

Curtis also is a long time builder and is correct in his statements. 26" wheel with 36 spokes is the typical setup with a coaster brake 1.5" hub rear. I look for 12 gauge spokes to give extra strength for use with a motor. Worksman steel wheels are my favorite brand but also more expensive. I've used other brands that were half the price and they worked fine, but need more frequent service and rebuild if lots of miles are put on them. Most of the cruiser axles are 3/8" so you want to measure the axles size on the Roadmaster to verify. Rear drop widths should be 110mm or so to hold a coaster hub front or rear. The steel stays can spread quite a bit if required to mount. A wide wheel is 2.125" but 1.95" is more common a wide tire can be mounted on a narrower rim but with kit motors chain clearance of the tire is often problematical to a novice builder. The use of a high quality hub sprocket adapter such as the Sportsman adapter helps in mounting larger tires and is less likely to slip on the hub and bend spokes. Beware the cut price bargain adapters. Manic is another quality brand but lacks a couple of features I like. On first builds tires 2.2" wide or narrower are pretty safe bets to clear the tire and stays with a straight chain line and as Curt indicated a strait chain line is what you must have on both sides of the bike, pedal chain and motor drive perfectly straight. So important and so hard to get the novice to accept as fact to a myriad of bad motor bike performance problems.

Run a 28" on the front and a 26" on the rear looks and feels strange...going uphill all the time it seems, but will work. Measure between the forks to make sure the tire width you select will work. 26" diameter is of course fine. Running a narrower tire up front than you use on the rear is also possible and is done from time to time. I'm not hitting all the points on wheel setup just some...others can add if required, but it's a start.

Best regards,

Rick C.
 
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vkray

New Member
Jun 26, 2020
12
13
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76
Vkray you ask what seems such a simple question or two about almost any part or step required for building a motorized bike and find that the answers seem to hinge around '" It depends" lol. So many variables involved due to the wide range of bike brands, styles sizes, materials, brakes and it goes on and on. Bear with us on this. Russel has built on the Roadmaster frame and he is a really good builder so I know these can motorize with a rag joint. I was hoping someone with direct knowledge of the frame you have will join in with a definitive answer for wheel and tire application using a hub adapter & appropriate wheel and tire combination and that would be ideal. In the meantime I'll add a bit to what's been said to this point.

Curtis also is a long time builder and is correct in his statements. 26" wheel with 36 spokes is the typical setup with a coaster brake 1.5" hub rear. I look for 12 gauge spokes to give extra strength for use with a motor. Worksman steel wheels are my favorite brand but also more expensive. I've used other brands that were half the price and they worked fine, but need more frequent service and rebuild if lots of miles are put on them. Most of the cruiser axles are 3/8" so you want to measure the axles size on the Roadmaster to verify. Rear drop widths should be 110mm or so to hold a coaster hub front or rear. The steel stays can spread quite a bit if required to mount. A wide wheel is 2.125" but 1.95" is more common a wide tire can be mounted on a narrower rim but with kit motors chain clearance of the tire is often problematical to a novice builder. The use of a high quality hub sprocket adapter such as the Sportsman adapter helps in mounting larger tires and is less likely to slip on the hub and bend spokes. Beware the cut price bargain adapters. Manic is another quality brand but lacks a couple of features I like. On first builds tires 2.2" wide or narrower are pretty safe bets to clear the tire and stays with a straight chain line and as Curt indicated a strait chain line is what you must have on both sides of the bike, pedal chain and motor drive perfectly straight. So important and so hard to get the novice to accept as fact to a myriad of bad motor bike performance problems.

Run a 28" on the front and a 26" on the rear looks and feels strange...going uphill all the time it seems, but will work. Measure between the forks to make sure the tire width you select will work. 26" diameter is of course fine. Running a narrower tire up front than you use on the rear is also possible and is done from time to time. I'm not hitting all the points on wheel setup just some...others can add if required, but it's a start.

Best regards,

Rick C.
Hey thanks Rich. I do thank you for your input, it is very helpful to me, believe, you me!
 
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indian22

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Dec 31, 2014
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Vkray I mentioned spoke gauge & would add 12 gauge is larger diameter than say 14ga. conversely 10ga. is larger and adds to the cost. Also brakes need be considered for the front wheel as well on this and future builds. The front brake is most efficient in stopping, I'll be brief here, weight is transferred as a reaction to the initiation of the stop to the front wheel while the rear tends to unload and lift. Mountain bike wheels with 3/8" bolt up for the front wheels are quite common and many have a wheel hub pre drilled for a disc brake rotor and a caliper adaptor can be easily and inexpensively added to your existing fork. I recommend. If you go this route ask questions that will smooth the purchase and mounting process.

If you decide to rely only on the rear coaster brake go slow and plan ahead. Two brakes are much better than one. If one brake is used the front brake is most efficient. I prefer redundancy with brakes regardless of the style of brakes selected.

Keep in mind that most any change made to the bike alters some other element or several elements of the build & overall safety and dependability should be kept in mind before and during each modification. Completed look need not be totally forgotten but form at times needs to be sacrificed for safety etc.


Rick C.
 
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