New to the forum - bike build

Kbone1

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Feb 3, 2017
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Hello everyone, I'm getting ready to start my first bike build. A little background, I grew up on motorcycles from riding to rebuilding, everything from dirt to street. I have a good mechanical and electrical background and am not afraid of improvising. I'm in my early 50's and have decided that all I need now is something to put around on and decided to sell my motorcycle and have some fun building a nice 4 stroke motorized bicycle. I have been slowly gathering decent components for my build and I would like some feedback from those that have done this. This is what I have so far: generic Gasbike frame from Gasbike.net, Manitou M30 forks, Shimano SLX M675 brake set w/205mm and 180mm rotors, 49cc 4G T Belt drive complete motor kit from bicycle-engines.com, DT Swiss EX 500 rims, Shimano Afine 8-speed internal hub, Shimano Alfine DH-S501 Dyno, Easton Haven 35 risor handle bars, and Michelin C4 Protek Max 26'' tires and tubes. Anyway, my first questions are:
Does anyone know of a good headset that will fit in this frame?
Does anyone know of good bottom brackets and crank sets that will fit on this frame?

Any guidance is greatly appreciated.
 
Hello everyone, I'm getting ready to start my first bike build. A little background, I grew up on motorcycles from riding to rebuilding, everything from dirt to street. I have a good mechanical and electrical background and am not afraid of improvising. I'm in my early 50's and have decided that all I need now is something to put around on and decided to sell my motorcycle and have some fun building a nice 4 stroke motorized bicycle. I have been slowly gathering decent components for my build and I would like some feedback from those that have done this. This is what I have so far: generic Gasbike frame from Gasbike.net, Manitou M30 forks, Shimano SLX M675 brake set w/205mm and 180mm rotors, 49cc 4G T Belt drive complete motor kit from bicycle-engines.com, DT Swiss EX 500 rims, Shimano Afine 8-speed internal hub, Shimano Alfine DH-S501 Dyno, Easton Haven 35 risor handle bars, and Michelin C4 Protek Max 26'' tires and tubes. Anyway, my first questions are:
Does anyone know of a good headset that will fit in this frame?
Does anyone know of good bottom brackets and crank sets that will fit on this frame?

Any guidance is greatly appreciated.
Hello and welcome. :)
Those parts sound like you put some thought into the bike that the engine is going on. :) Building your own wheels too? Awesome! Those rims, ooh la la! Using DT Swiss Alpine iii's I expect? :)
I have decided to give Shimano brakes a try, too. Not sure why I did, haha. I haven't fitted them yet and bike is far from ready so I can't give an opinion on how well they work. You will certainly need the shortening kit though. I'm going to get the barb and olive off eBay, and bleed kit too. Make sure you get the right version of each!
Of course using hydraulic rear brake with a single crown fork means that the hose is vulnerable to bar spinning crashes so I can recommend keeping the gear cable slightly shorter than the hose so it pulls tight first. Also getting a Gusset hole in the head or similar (Neko, etc) hollow BMX headset top cap and bolt so you can run the front hose through it and protect your front brake in case of a crash. That way you'll always have the front even if the rear hose gets damaged.

I'm surprised by the questions at the end of your post, to be honest. All those components sound ideal for a jackshaft build using the Sick Bike Parts 4-stroke Shift Kit, which comes with the jackshaft, cranks, bottom bracket and chainrings you need to get the engine and pedal power to both run the through the right hand side and the 8 speed hub. Sure, it's expensive, and actually it is delaying my first build right now haha, but I'm sure it is well worth saving up for. :)

I don't know the frame, think I have read that it's a semi integrated headset that you need?

Good luck with your build and I hope you will post pictures when it is all done! :)
 
It seems like you have a big budget for this project. I would suggest three things. Not entirely certain about #2 requirements but maybe Randall or someone with them can speak to them. I think they are great.

- As a beginner, I would just start with the default direct drive kit and then after using the bike for a few months decide if you want to put on a SBP shift kit for added fun and gearing.
- I really like the wheels with solid spokes (though I never used them...) because #1 eventually the chain and chain tensioner is going to go into your spokes and the solid spokes will not be damaged by the chain and #2 I dont think the wheel will get warped by the torque from the engine so require no truing. Maybe, I'm wrong about the two but that is my assumption versus the traditional spokes. Here is Randall's bike with the solid wheel spokes but NOTE YOU WILL NEED AN ADAPTER AND POSSIBLE SPROCKET FOR WHEEL.
26123.jpg

- There are many options for the 4G in terms of gearing. Take a look at KC's chart below to see which works best for the riding terrain in your area, your weight, and speed expectations.

4Gratios.jpg
 
Hello everyone, I'm getting ready to start my first bike build. A little background, I grew up on motorcycles from riding to rebuilding, everything from dirt to street. I have a good mechanical and electrical background and am not afraid of improvising.
I'm in my early 50's and have decided that all I need now is something to put around on and decided to sell my motorcycle and have some fun building a nice 4 stroke motorized bicycle.
I have been slowly gathering decent components for my build and I would like some feedback from those that have done this.

Welcome Kbone, I am in my 50's as well and from your parts list you are after what I was, a cool quality commuter.

I am a custom builder in Phoenix and pretty much dedicated to 4-stroke shifters these days so I can help you before you even get started if you want a bike like this.
http://kcsbikes.com/topic.asp?TOPIC_ID=982

2_Copper10GDoneLeft-1280.jpg


First and foremost send that fake gas tank frame back and use a real Grubee!
http://www.bicycle-engines.com/Grubee-Aluminum-Motorized-Bicycle-Frame-GTA.html

Besides better material and workmanship, it has things the knock-offs haven't copied yet like back wheel disc brake bosses.
If you have $ from a motorcycle sale you can build one hell of an MB ;-}

This is what I have so far:
SLX M675 brake set w/205mm and 180mm rotors.
49cc 4G T Belt drive complete motor kit from bicycle-engines.com
Shimano Afine 8-speed internal hub

Anyway, my first questions are:
Does anyone know of a good headset that will fit in this frame?
Does anyone know of good bottom brackets and crank sets that will fit on this frame?

Any guidance is greatly appreciated.
The trick to build for me was was to to find a bicycle with all the parts I wanted for less than buying them separately, so I use a FITO 7-speed.
http://www.bikebuyers.com/fito-modena-gt-alloy-7sp-men.htm?gclid=CJnmwsCw2NACFciCfgodem8IlQ

I strip it down to the frame and have all the parts to build bikes like this on the gas tank frame.

RedGT2done2L.jpg


I am thinking that is what you want too ;-}

I think that 8 speed Alpine is a waste of money, you just don't need that many gear ratios with and engine, heck I find a 3-speed sufficient but I am really liking the SA disc brake internal, it does expand the high end overdrive a bit.

Enough for now, but you get the idea ;-}
 
I have the same frame. It is 1 1/8" threadless headset. I have a 49cc 4 stroke. I had to go with the 153mm bottom bracket from sickbikes. It an offset bracket and gasbikes extra wide cranks. Most people on here are gasbike haters. Don't let it bother you. It's a great frame. With everything in this hobby you can drive yourself nuts with unforseen things that come up. There are even ways to use disk brakes on this fram. I have worked out most issues you will come across. So feel free to ask away. I was not going to post pictures until it was completely finished. But what the hell. I'll post some pics tomorrow.
 
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Hello and welcome. :)
Those parts sound like you put some thought into the bike that the engine is going on. :) Building your own wheels too? Awesome! Those rims, ooh la la! Using DT Swiss Alpine iii's I expect? :)
I have decided to give Shimano brakes a try, too. Not sure why I did, haha. I haven't fitted them yet and bike is far from ready so I can't give an opinion on how well they work. You will certainly need the shortening kit though. I'm going to get the barb and olive off eBay, and bleed kit too. Make sure you get the right version of each!
Of course using hydraulic rear brake with a single crown fork means that the hose is vulnerable to bar spinning crashes so I can recommend keeping the gear cable slightly shorter than the hose so it pulls tight first. Also getting a Gusset hole in the head or similar (Neko, etc) hollow BMX headset top cap and bolt so you can run the front hose through it and protect your front brake in case of a crash. That way you'll always have the front even if the rear hose gets damaged.

I'm surprised by the questions at the end of your post, to be honest. All those components sound ideal for a jackshaft build using the Sick Bike Parts 4-stroke Shift Kit, which comes with the jackshaft, cranks, bottom bracket and chainrings you need to get the engine and pedal power to both run the through the right hand side and the 8 speed hub. Sure, it's expensive, and actually it is delaying my first build right now haha, but I'm sure it is well worth saving up for. :)

I don't know the frame, think I have read that it's a semi integrated headset that you need?

Good luck with your build and I hope you will post pictures when it is all done! :)
Well, I have been told that I do not communicate well, so I have already purchased the parts I listed earlier. These are the pics of what I have, I just need to find some 13 gage spokes and a seat.
 

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It seems like you have a big budget for this project. I would suggest three things. Not entirely certain about #2 requirements but maybe Randall or someone with them can speak to them. I think they are great. .
*** No big budget, I have just been buying parts I like when on sale, besides, I have still spent less money than I did on a Kymco Agility 50 that I had a couple years ago. You also can’t beat the personal satisfaction of your own build!

- As a beginner, I would just start with the default direct drive kit and then after using the bike for a few months decide if you want to put on a SBP shift kit for added fun and gearing..

*** It must be true that I do not communicate well, so..., I have already purchased the parts I listed earlier. The Shimano 8 speed hub will be my transmission. If everything fails to be what I expected then I am only out the cost of a frame and can use the parts on a good mountain bike frame.

It seems like you have a big budget for this project. I would suggest three things. Not entirely certain about #2 requirements but maybe Randall or someone with them can speak to them. I think they are great.

- As a beginner, I would just start with the default direct drive kit and then after using the bike for a few months decide if you want to put on a SBP shift kit for added fun and gearing.
- I really like the wheels with solid spokes (though I never used them...) because #1 eventually the chain and chain tensioner is going to go into your spokes and the solid spokes will not be damaged by the chain and #2 I dont think the wheel will get warped by the torque from the engine so require no truing. Maybe, I'm wrong about the two but that is my assumption versus the traditional spokes. Here is Randall's bike with the solid wheel spokes but NOTE YOU WILL NEED AN ADAPTER AND POSSIBLE SPROCKET FOR WHEEL. ***I do like aluminum rims I just don’t like the swirled spoke look, also I cannot mount my hubs in them.
26123.jpg

- There are many options for the 4G in terms of gearing. Take a look at KC's chart below to see which works best for the riding terrain in your area, your weight, and speed expectations. **** Thank you for the gearing guide, this will be great!

4Gratios.jpg

- I really like the wheels with solid spokes (though I never used them...) because #1 eventually the chain and chain tensioner is going to go into your spokes and the solid spokes will not be damaged by the chain and #2 I dont think the wheel will get warped by the torque from the engine so require no truing. Maybe, I'm wrong about the two but that is my assumption versus the traditional spokes. Here is Randall's bike with the solid wheel spokes but NOTE YOU WILL NEED AN ADAPTER AND POSSIBLE SPROCKET FOR WHEEL.
26123.jpg

- There are many options for the 4G in terms of gearing. Take a look at KC's chart below to see which works best for the riding terrain in your area, your weight, and speed expectations.

4Gratios.jpg
 
Thank you KC vale for your input and willingness to help. I have already bought almost everything, and as far as the 8 speed being overkill and a 3 speed would be fine. Well that’s your choice, but since I could not find a 3 speed with 1st gear being around 50% under drive and 3rd gear being around 50% over drive, I did not get it. The way I see it, more gears, more terrain options. Even If I could find a 3 speed with that ratio I don't think that little engine could handle that big of gear ratio spacing, but this is my first build. Im sure I will have questions for you as I start my build.
 
Well, I have been told that I do not communicate well, so I have already purchased the parts I listed earlier. These are the pics of what I have, I just need to find some 13 gage spokes and a seat.
Oh I understood that you already bought those parts.
Idk what you need 13 gauge spokes for. Alpine iii are triple butted. 13 gauge at the head, 15 gauge in the middle where you don't need thickness, and 14 gauge at the threads so they use the better pitch. They are high quality: and without flaws there's little chance of breakage.

Cut and paste from Sheldon Brown without permission:
"Triple-butted spokes, such as the DT Alpine III, are the best choice when durability and reliability are the primary aim, as with tandems and bicycles for loaded touring. They share the advantages of single-butted and double-butted spokes. The DT Alpine III, for instance, is 2.34 mm (13 gauge) at the head, 1.8 mm (15 gauge) in the middle, and 2.0 mm (14 gauge) at the threaded end.

Single- and triple-butted spokes solve one of the great problems of wheel design: Since spokes use rolled, not cut threads, the outside diameter of the threads is larger than the base diameter of the spoke wire. Since the holes in the hub flanges must be large enough for the threads to fit through, the holes, in turn, are larger than the wire requires. This is undesirable, because a tight match between the spoke diameter at the elbow and the diameter of the flange hole is crucial to resisting fatigue-related breakage.

Since single- and triple-butted spokes are thicker at the head end than at the thread end, they may be used with hubs that have holes just large enough to pass the thick wire at the head end."
 
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