I just got a Yamaha qt50  By  ilovenxstage (Read 7,343 times)

No air filter

Odometer

Reminds me of my youth as a couple of buddies had one as I was riding a Honda Urban Express and later a ton of pedal types as my father and I bought up all of a local shops surplus as he wanted to get out mopeds and focus more on Husvarna TT racers . No air filter it will be too lean to run , bog beyond usable , and get dirt into the carb . Finding an original airbox may be hard to do and you might opt for a Uni or K&N style or other after market one . Remove the jets and see if they are listed on the chart www.jetsrus.com/FAQs/FAQ_identify_that_jet.htm as you surely want to go up a bit larger but just lil bit . I tried a larger main jet on a Tomos Golden Bullet and it actually went slower as it was stock .

These type do not have a CVT and most are slow on take off but have better performance at midrange and get killer MPG as you can run WOT all day long , but go slow up hill . Make sure to use decent 2T oil instead of weed eater junk . I like Maxxima 2T synthetic blend as its around 10 a quart and barely smokes when you do a cold start , where when I ran weedeater stuff as a pup it would leave a com trail and foul out the plug . A simple remove and hit with carb spray and wipe clean and check the gap was under 5 minutes as most are in the open with no cover or panel to remove . I would inspect the chain and cogs for wear . May get lucky and find OEM parts and unsure if you can get choices in teeth amounts on these unlike MX motorcycles have plenty . The frame is light and ok for a light rider but may need tweaking for hot rod mods and a heavy rider .

What is the engine stamp code ?

These are great for around the block or short trip rides , as well as on college campuses , way more reliable than a Chinese scooter , but limited on power and speed . If you could find a pipe with an expansion chamber and maybe do custom porting with a Dremel and CF or FG reeds and again more upjetting might be able to get more RPMs out of it .

Here is more links www.sip-scootershop.com/en/main/base/home.aspx www.mopedarmy.com/ www.mhr-usa.com/

What would be cool if you could find and more so if it would fit with no or little mods , Tomos made a 2 speed auto tranny that shifted like a Chevy Powerglide . I had 3 of em and take off and uphill was better except a not so steep hill it would shift up and down more than it should .

Hope you get it going and post with happy news

I know nothing about 2 strokes. Since there are no valves to come out of adjustment, what could cause low compression, besides bad rings? I read where you could put a small amount of oil down the spark plug hole and the oil would temporarily seal the bad rings and briefly restore compression. I tried that and it still has very weak compression. I'll let it cool, find my ancient compression tester and check what the compression is. Also, does anyone know if there are any high flow air filters available for these bikes? I know it has a Mikuni carb, but I don't know what aftermarket parts are available. I also need a new kill switch. I accidentally gave myself a nasty shock when I touched where the exposed wire goes into the brake lever. Also, how do you take apart the brake drums to get to the shoes? And one more question, There is a spot for a battery, but what does it power? There is no electric starter and all the lights are powered off the magneto (unless that was a mod that one of the previous owners did). By the way, this is a 1980 model.