Spokes breaking

Gastrike 9

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I built a Schwinn meridian gastrike (on another post) with a 79cc 4-stroke and the transmission just recently added... No rag joint as I use cnc hub adapters and sprockets... The bike rim spokes were replaced with heavy duty spokes... I'm at a loss of why spokes keep breaking and what to do about it...
 
Breaking spokes indicate a poorly built wheel. Everything is out of wack.
If one spoke is loose or the rim is bent other spokes take up the slack and break.
You say you had the bike rim replaced with heavy duty spokes. The rim metal itself may be fatigued that will cause spokes to break.
If your a heavy guy that puts extra stress on the spokes too. Best to buy a New Heavy Duty Wheel.
 
Or, your adapter is loose on the hub.


Breaking spokes indicate a poorly built wheel. Everything is out of wack.
If one spoke is loose or the rim is bent other spokes take up the slack and break.
You say you had the bike rim replaced with heavy duty spokes. The rim metal itself may be fatigued that will cause spokes to break.
If your a heavy guy that puts extra stress on the spokes too. Best to buy a New Heavy Duty Wheel.
 
Where on the spoke are they breaking? Near the nut, in the middle or near the 90deg bend?
 
Unless you're using double walled rims and a truing stand to build the wheel failure is inevitable. If a really strong wheel is what you're after use a 36 spoke 12 gauge cross 4 pattern on double walled rims. You'll also need 36 hole 12 gauge spoke hubs, a truing stand and possibly a dishing tool. You could also have a reputable bicycle shop build the wheel for you. Yes it'll be expensive but a good set of wheels can be worth their weight in gold.
 
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Spokes are Breaking at the hub in the bend... Only 2 of them broke and the hub adapter isn't slipping... I have marks on that to check and they haven't moved atall... I am not too heavy at 160lbs... I had the spoke work done at a competent bike shop... It's possible to take turns too fast causing spokes to break ?.. That don't make sense either cause if that causes it then spokes on both back wheels would break I think... It only happens on the engine side drive wheel... Maybe motorcycle spokes will be better?..
 
Spokes are Breaking at the hub in the bend... Only 2 of them broke and the hub adapter isn't slipping... I have marks on that to check and they haven't moved atall... I am not too heavy at 160lbs... I had the spoke work done at a competent bike shop... It's possible to take turns too fast causing spokes to break ?.. That don't make sense either cause if that causes it then spokes on both back wheels would break I think... It only happens on the engine side drive wheel... Maybe motorcycle spokes will be better?..

You never said what gauge spoke being used. Chances are they're 14 gauge spokes. I once had the same issue with them breaking at the right angle bend. All spokes aren't created equally. I had to buy high quality spokes which cost around 3 times the amount of the cheap ones. This fixed the problem.
 
I'm not an expert but it would seem torque on the spokes is the culprit, twisting motion of the hub via the spokes. 79cc is rated 3hp and that's a lot of twisting motion for spokes designed for human power alone, max 1/3rd hp. Maybe those 2 spokes were tighter than all the others and taking more force than the others, all should be torqued equaled to share the load equally. Are the steel spokes, aluminum or SS? If aluminum alloy you know the answer to that one. Anyways just thinking and not sure of the solution. How many spokes per wheel? What size wheels in the rear?
 
You never said what gauge spoke being used. Chances are they're 14 gauge spokes. I once had the same issue with them breaking at the right angle bend. All spokes aren't created equally. I had to buy high quality spokes which cost around 3 times the amount of the cheap ones. This fixed the problem.
12g would be a lot stronger IF needed.
 
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