Help on coaster brake self destructed

[Turtle Tedd]

While riding today,not very fast at all,applied rear coaster brake easy a few time and it would all of a sudden grab hard ..did this a couple of times...couple miles later heard a loud clunk...when I took a look the brake arm was bent in half,pretzal like ,but still attached to the frame by the clamp and working...When I got home I pulled off the wheel..the axle is wobbleing around big time..I guess the bearings and rest of the chinese parts in there are toast...been reading all the posts on coaster brakes ...This bike is a new shwinn del mar...I dont know if I should have it rebuilt....I don't mind spending the cash for good parts but on the other hand I do not want to spend a dime on a rebuild thats only going to last 50miles....Need some of you guys experiance and sugestions here....will wait till tuesday or wed to take it in...what do you all think'whats my options

 

[duivendyk]

Poor dumb TT,don't mess with ANY brakes coming from China and least of all any coaster brakes,or are you anxious to get to the Pearly Gates ASAP,then keep right on going.

 

[Turtle Tedd]

duivendyk for whats in your brain thats not much help..after all this is a motorbike building forum...its been fun insulting each other on the white zone but I need some expert info here...what you got....haven't really read all your posts..have you built any of these HT motorbikes? gimmy some info,sugestions..need some possitive feedback here

 

[icyuod2]

if a coaster arm is not attached to the frame, the exact same things you described happen.

the coaster won't seem to work, then it grabs hard. at the same time the arm will rotate loosening the hub (making the wheel wobble) this however usually does not happen if the arm is attached to the frame.

so chances are the reason your wheel is wobbly is because the coaster brake has loosened the hub. i imagen if you turn the bolts (inside your drop outs, that the wheel will be right as rain (excluding the bent coaster arm)


i would love to see a pic, i cant imagen how you'd bend the brake arm before tearing the little coaster arm clamp from the frame. it is rather puzzling.

 

[Turtle Tedd]

icyuod2 the coaster arm was still attached to the frame after this happened . It never did tear loose just slid down as somehow the arm bent..puzzling for sure..cannot send pic at this time

 

[give me vtec]

thats one reason why I would never use a wal mart bike... I wouldnt even trust it to pedal down the street, let alone with an engine. I wanted to do a black del-mar but changed my mind when I got to wal-mart and rode it around the store for a minute.

 

[Just_Gasit]

I smoked a coaster brake on a cruiser on a long down hill road. I tried real hard to keep the speed down and waited for time to time stopped to let it cool off. Near the bottom, I pushed it and it started to grab hard, when I stopped, the hub was black and sizzled when I poured some water on it. I never used it again and traded the whole bike for a couple of tubes for another bike at the bike shop. Motorizing a bike with only a coaster brake is risky and not advised. You can fix your coaster brake but add more brakes.

 

[icyuod2]

did one of the bolts on your rear sprocket catch the coaster arm?
i imagen that would fold the arm in 1/2 while still attached to the frame.

 

[bamabikeguy]

I don't mind spending the cash for good parts but on the other hand I do not want to spend a dime on a rebuild thats only going to last 50miles....Need some of you guys experiance and sugestions here....will wait till tuesday or wed to take it in...what do you all think'whats my options

So, the DelMar is a single speed/coaster? I've read folks saying they've used that model, but never investigated it, (I thought it was the 7 speed equivalent of the Jaguar/PointeBeach, maybe from K-Mart). You can change a 7 speed into a single relatively easy, to do the reverse is tough, because of the cabling and finding a spot to bolt on the hand brakes.

Those two, Jaguar and PointeBeach, are good starter bikes, in the $150 range.

If you'll put up your closest Craigslist bike postings, we might be able to spot a suitable used bike to motorize, save you some bucks.

What has me puzzled TT is whether you were using the DelMar's 16 gauge wheel in your build, or had you purchased a 12 gauge wheel like the MB forum has been recommending since the beginning?

 

[HoughMade]

I would go ahead and rebuild it. Before I ever used my new rear wheel, I disassembled the coaster hub and greased the bearings myself and other hub parts. I have heard bad things about the state of lubrication of new bikes. I am guessing the breakdown of the brake was more due to inadequate grease than any inherent problem.

That being said, Once it is rebuilt, I would fit caliper brakes- should be pretty easy. Save the coaster for the back-up plan, not primary braking. That's what I do.