QT50 tires and brakes

What’s the best upgrade I can buy for my QT50?

Every bike is different but generally they all need new tires. A mechanic once told me that the most important part of your car is the part that hits the road. Same thing can be said for your QT50. Chances are it has 30+ year old tires on it that are cracked and dry-rotted. I’ve had a couple with bald rear tires as well. A popular tire for the QT50 is the IRC NC 77. You can put it on both the rear and the front. You’ll want to get size 70/90-14-34-P for both the rear and the front. The 80/90 is definitely too big for the front but will work on the back but you will lose the rear fender because of the tire width.

If you use the IRC NC 77 on the front, you will need to adjust the fender stays so that the tire will not rub them. Kenda makes a 14″ tire that will work on the front but it is difficult to find. Other front tire options are the irc inoue tire – 14″ x 2.25 hod rodddder and the vee rubber VRM 020 moped tire – 14 x 2.25.

New tires improve the ride, handling and the braking. Anymore, it’s the first thing I change when I get a “new to me” moped.

My brakes seem loose on my QT50. What can I do to tighten them?

If you have too much play in your brake levers, you can tighten them up with the cable adjusters at the handlebars or at the wheels. At the handlebars, simply make the cable housing longer to tighten up the levers and eliminate play. Then screw down the locking nut (usually black plastic) to keep that setting/adjustment. At the wheels, you need to tighten the adjusting nut to make the spring shorter to eliminate play in the levers and push the brake pads outwards towards the hub. After you have made adjustments, roll your qt50 along and see if the pads are catching the hubs. If so, then back off your initial adjustment.

At some point, you won’t be able to adjust your brakes further because the pad is too worn. You can find a new set of brake pads for both the front and rear brakes on a qt50 here. You can find the same pads on eBay for cheaper.

Pads for the PW50 are even cheaper but they are a little too big. You could file them down if you wanted and make them fit. Wear some sort of mask to protect yourself from the brake dust. Although I doubt the new ones are made from asbestos, brake dust, no matter what it is made of, is not good to breath in. I talk a little bit about replacing rear brake shoes here. Your main issue will be getting the spring back on. I haven’t done it for awhile so I forget what my exact technique is.

My rear wheel is seized and won’t budge. What is wrong with my qt50?

First thing to check is the rear brakes. You can loosen the nut at the end of the rear brake cable and see if that helps. If not, it’s likely that your bearings are frozen up (see above picture). If your qt50 sat out in the weather quite a bit, that is most likely the case. Water probably got to the bearings and rusted them up. You can usually find a set of new bearings on ebay along with the special tool needed to remove them – all for around $30.