So that's what happens when you accidentally clutch dump and your hub adapter slips...

extremeodd

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Mar 30, 2019
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121
Lately I've been getting braver and braver for how far I travel on my bike, so yesterday I decided to do a rough 12 mile journey to enjoy the beautiful weather. Everything was going smoothly until when I was taking off from a light I let go of the clutch too early causing it to almost stall. In an instant I grabbed the clutch, grabbed the throttle hard and managed to hit a small pothole which caused the clutch lever to slip. Heard a nice loud pop and the bike locked up. So after walking it across the intersection I took a closer look. The wheel was so out of round that it had gotten stuck on the rear brake, 2 spokes were snapped and several others bent. After disconnecting the rear brakes the bike was able to roll again and that worked for maybe about 10 seconds before the 91f heat started to get to me. Considering that I still had just over 4 miles until I got home, I risked using the motor. That, by far, was the sketchiest bike ride of my life with how bad of a wobble the wheel had. 7-9mph was the best you could do without being overcome by sheer terror.

I blame not the hub adapter, but myself for not cleaning and severely roughing up the mating surfaces. The only time it would shift is if you dumped the clutch to kill the motor or if you had it on a stand, in gear and cut the motor. It never, ever moved from just acceleration. A testament to how well they can hold at times.
 


JerboaJohn

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Jul 29, 2018
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1,272
yeah, there's a needed thing to keep in mind these are not a usual clutch we can slip and power up to speed. all or nothing and only when the motor is at a rpm it csn handle a load. once I almost went over the bars bcs I had 2 left levers, and grabbed the wrong one and these events likely happen at intersections.
a freewheel would solve many problems but then you can't bump start. 4 strokes have a big advantage on any situation under 8mph I think esp. braking and accelerating from a stop.
you're ok tho? I pushed my heavy bike 3 miles 1 time on a flat tire. glad it wasn't vey hot!
 

extremeodd

Active Member
Joined
Mar 30, 2019
Messages
121
you're ok tho? I pushed my heavy bike 3 miles 1 time on a flat tire. glad it wasn't vey hot!
Yeah, it was just kind of a shock. A loud bang and the tire instantly locked but I was basically stopped anyways. All I had to do was disconnect the brakes and was able to ride home (albeit slowly) under motor power.

This one small event has lead to so much damn stress. In my mind, I figured bikes flow like water in the PHX area so how hard would it be to get one under $50 with a good wheel and a 1in hub. Harder than one might think when you don't have readily available transportation. That and 27.5s arent super common so I had to settle with looking at 26s.

Long story short, I got scammed for $45 "the wheels are perfect, just needs the rear brakes" and the f***ing wheel is bent. That was my idiocy due to having him bring it by the house and him arriving 5 mins before a company skype meeting so I didn't take a close enough look. Whatever, I have his home address. Later that day got a ride to get a $25 bike that had promising looking wheels and that one is actually a really good bike. Except for the hub is roughly .2mm too small for the hub adapter to grip. The gap is the same thickness as approx 3 sheets of cheap aluminum foil, I'd try to rig something up but I dont have any sheet metal that thin and aluminum foil will just slide and I cannot use JB weld as this is only to be used for a short time, hub adapters aint cheap.

As a great man once said
Kenny Rogers said:
You've got to know when to hold 'em
Know when to fold 'em
Know when to walk away
So I'm throwing in the towel on replacing the damn wheel for now and just taking the damaged one to the bike shop to replace 12-15 spokes, true it up, and maybe have them repack the grease and rough up the hub (so the adapter won't slip again). That's going to be $60-75 and yet more time with the bike down but at this point I'm sick of the stress. Might throw the ol rag joint adapter on the one good 26in wheel I have to ride but then I wont have rear brakes however I would be able to get my new KTM50 carb (PHBG) installed and tuned while waiting on the shop to finish my 27.5.
 

CrazyDan

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Jul 9, 2016
Messages
2,027
Rear brakes are over-rated. I rarely find myself using them. If I ever go single speed again, I'm using a disc brake mounted sprocket, or one of them hubs that has threading for freewheels on both sides. Too many issues with every other mount type.
 

extremeodd

Active Member
Joined
Mar 30, 2019
Messages
121
The plot thickens, then thins out enough to be unsatisfying. Took the wheel up there, they told me even though only some of the spokes are bad they would have to rethread the whole thing. Just over $100 which is $30 shy of buying another brand new version of the bike that comes with not one, but 2 wheels! So I had the thought of cleaning the wheel up, buying the walmart bike, swapping the wheels (and tires, they wouldn't believe that much wear in 2 days) and bringing it back saying its junk. But thankfully the salesman piped up saying they have used wheels and found a 26in with a 1in hub that was just perfect for my needs. Plus it was only $30! So I grabbed that, a tire and an inner tube for $73 out the door. Probably could have gotten cheaper tires/inner tube but they both were puncture resistant and that should justify the cost. Got it all assembled, filing some grooves into the mating surfaces of the hub/hub adapter to help with slippage + a couple of drips of locktite blue (I know I need green for that), tire is on, inner tube installed.

Now I'm just waiting on my neighbor (who gave me the ride) to be done working for the day so I can borrow his air compressor for 20 seconds to air the tire up and slap it back on the bike. Then I should get around to removing the remnants of the rear brakes and swapping the dual pull lever back to a single pull. Hopefully tonight I can start getting this PHBG carb dialed in, curious to see if I gain anything over the stock NT.


EDIT: Well, hell. Bent the spokes a touch already. Was kick starting the f*** out of the bike trying to get it to start with the new carb and on my hardest try it fell from the stand and basically acted like a light clutch dump. The CNC mount shifted just enough to bend the adjacent spokes. Should be fine, I just gotta be super careful not to do any clutch dumps/sudden severe shocks to the drivetrain. If/when I break this wheel, I'm going to JB weld the adapter in place on the next $30 wheel.
 
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