Stopping 23" tires

[Helirich]

I have 23 or 24" tires. I was doing some testing today and the brakes suck. There is no chance of locking up the wheels even if I stand on em. Right now the cart is 36V, but I'm upgrading to 48. I can only imagine how bad they will be when I can go over 20 mph.

Is the poor stopping because they are out of adjustment or are those tires just too big for those little drums? I pumped them fifty times hopping to click the self adjusters. (Same after.) I recently had the drums off and I think they are adjusted pretty good. But I'm pretty new to cart world.

I need to know quick because I'm thinking of ordering a new controller. (Might as well fill up the box for shipping.)

[dougs_huntingcart]

Physics. momentum= mass x velocity . It takes more to stop a taller tire and you're talking about adding more velocity.
I'd fill that box with a nice front brake set.

[Epb]

Rear discs are great! Some sponsors sell them.

[cgtech]

Disconnect the cables at the brakes to adjust the brakes. Many people adjust only at the pedal, which eventually leads to the brake lever geometry being poor & lame brake performance. Or, just buy some discs, and never look back.

[Sir Nuke]

Originally Posted by Helirich

I have 23 or 24" tires. I was doing some testing today and the brakes suck. There is no chance of locking up the wheels even if I stand on em. Right now the cart is 36V, but I'm upgrading to 48. I can only imagine how bad they will be when I can go over 20 mph.

Is the poor stopping because they are out of adjustment or are those tires just too big for those little drums? I pumped them fifty times hopping to click the self adjusters. (Same after.) I recently had the drums off and I think they are adjusted pretty good. But I'm pretty new to cart world.

I need to know quick because I'm thinking of ordering a new controller. (Might as well fill up the box for shipping.)

3 yrs ago, when I rebuilt my cart, I ask the same question. I too have 23" tires....and I'm at 36v....and I run 27 mph flat out. and I inly have the stick brakes, still. and have NO PROBLEM stopping, or even locking them up if required.

When I rebuilt my cart, it also included the brakes. cleaned everything up, took any glaze off of the drums with some sandpaper, replaced all the shoes and springs....and adjusted the brakes per the manual. STOPS ON A DIME.

[Helirich]

I just had mine apart (installed a limited slip) and the shoes and drums look fine. I adjusted them real close. My cart only does 18 mph flat out right now. But I expect 24 after the conversion. (Maybe) I don't need any faster than that.

The rear discs seem like an easy job. But I have to admit, front discs would probably be more effective. If Sir Nuke can stop, maybe I should take another look.

Question, I adjusted the brakes with the little "one way" clickers inside the drums. Is there another way?

[Sir Nuke]

well like cgtech mentioned, disconnect the cables, then adjust the brakes as close as possible, then reconnect....then if need be, adjust the Equalizer Link and or Compensator Assembly under the floor where it connects to the brake pedal.

[JohnnieB]

To get the auto-adjuster to adjust the brake shoes, drive the cart forward at cruising speed, brake hard and then take foot completely off pedal just before cart stops. (Cart must be in motion for auto-adjusting to occur - See attached cut&paste from service manual.)

Repeat the process until you can lock up the tires.

If you cannot get the tires to lock up, fix or replace the brakes.

If you can get the tires to lock up, you will not get any more stopping power with rear wheel only disc brakes.

However, disc brakes will reduce brake fade in high usage situations.

Of course, going to four-wheel disc brakes will more than double stopping power.

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I'd love to install four-wheel hydraulic disc brakes, but I cannot because nobody makes any that will work with 8" rims, so I routinely use regen braking to slow my cart to <15 MPH before applying the mechanical drum and shoe brakes. If need be, I can stand on the brake pedal and slide the tires at any speed.

In fact, when safe to do so, I don't use the mechanical brakes at all since my XCT controller will actually stop the cart using a combination of regen braking and plug braking.

The DCX controller I was using prior to upgrading to the XCT, wouldn't completely stop my cart with regen braking, but it would definitely slow it down into the speed range the puny stock brakes were designed for.

[scottyb]

Also not the weight of the wheel & tire is more a factor than size. Steel wheels which are heavier than Aluminum wheels require more force to stop. Same goes for tires..... weight varies by size and design.... 4 ply as opposed to 2 ply etc. These are all factors to look at when evaluating breaking force needed.

[Helirich]

Thanks again Johnnie B, I was not doing it right. (I was stopped)

I just took a ride on my Marithon. It will lock the wheels. They aren't as big as the TXT, but it's obviously stops better. I'm still modifying the TXT, but I will do the moving adjustment when I get it going next.