Available at Brennys Motorcycle Clinic in Bettendorf, Ia. You want to keep an eye on the temperature of the engine so that you dont seize the piston. Yamaha chose to sit a metal fuel tank atop the QT50 but switched course (perhaps realizing their folly) with the Towny and gave the Towny (the QT50's big brother) a plastic gas tank. It has the exact same wiring and driveshaft as the QT50 and the same 2 speed automatic engine as the Chappy. #29-3208 | Yamaha QT50 (1979-1987) Front Brake Shoes Pk/2 Diameter: 79.3mm Width: 17mm OEM Ref # 27V-W2535-00 USD$ 5 .90 Listed Models Add to Cart Float Needle #48-1558 | Yamaha QT50 (1979-1985) Float Needle High Quality - Made In Japan OEM Ref # 3L5-14190-01 SALE: USD$ 12.00 (USD$ 19 .95) Add to Cart Universal Glas-Pak Insert #009-0317 Ill repeat that: Prices vary throughout the country so this is just a general guide. (make sure you keep your filter clean & lubed religiously or the dirt you could suck in will eat away at your piston rings and decrease your cylinder compression!!) If it is a complete mess, chances are the inside isnt much better. In addition 60cc top ends are prevalent on ebay and amazon. Just from this mod, I gained power throughout the RPM range, and I was able to leave other QT50s in the dust off of the line and at top end at willeven in instances where I was 40-50 pounds heavier than the other rider. Titled and ready to go. Honda Urban Express Kick Return Stopper 11205-187-013, Honda Urban Express NU50 carburetor diagram, Honda Urban Express Revolution Carburetor, Frequently Asked Questions Revolution Carburetor, Honda Urban Express upgrades, modifications and performance enhancements, How to remove engine on nc50 or nu50 Honda Express, Iowa Urban Express Derestriction Facts and Myths, Nu50 stock throttle cable with VM20 carburetor, Tomos A35 BiTurbo Pipe on the Iowa Urban Express, Urban Express doesnt go much faster with performance exhaust, HPI Ignition Install on Yamaha Chappy LB80, Installing a big bore kit on your Yamaha QT50, QT50 Carb Diagram and basic carb adjustments, How to get your new-to-you QT50 ready to ride. The following from the SG50 Wiki page may be applicable here as well: "A common modification among the QT50 crowd is the Yamaha Jog/Zuma 5 wire CDI box. This page was last edited on 13 January 2018, at 17:44. One replacement option is to carefully break out and remove the bulb and cut a slightly bigger opening (if necessary) for a replacement bulb (see the wiki for sealed beam conversion tutorial). yamaha qt50 big bore party pack with pretty much all the stuff you need! Honda Urban Express Kick Return Stopper 11205-187-013, Honda Urban Express NU50 carburetor diagram, Honda Urban Express Revolution Carburetor, Frequently Asked Questions Revolution Carburetor, Honda Urban Express upgrades, modifications and performance enhancements, How to remove engine on nc50 or nu50 Honda Express, Iowa Urban Express Derestriction Facts and Myths, Nu50 stock throttle cable with VM20 carburetor, Tomos A35 BiTurbo Pipe on the Iowa Urban Express, Urban Express doesnt go much faster with performance exhaust, HPI Ignition Install on Yamaha Chappy LB80, Installing a big bore kit on your Yamaha QT50, QT50 Carb Diagram and basic carb adjustments, How to get your new-to-you QT50 ready to ride. This is the trade off for more top speed. 1. Popular modifications include: Yamaha YT60 cylinder, piston and rings. What should you pay for (or sell) a Honda Express? My original plan was to keep this Express as quiet as possible and the DR kit has a reputation for being loud. Damn that was sweet! I replaced both crank shaft bearing seals prior to installing the kit. Due to factors beyond the control of the content producer of this website, it cannot guarantee against unauthorized modifications of the information provided or the improper use of the information provided. I achieved a top speed of 39.7mph which I consider amazing on a stock cylinder. Remplacement pour Yamaha QT50 1979-1987 ; . Hey, so do I. I'm running a 60cc top end on my QT with the Towny bottom end. Swap in a slightly smaller main jet, a less restrictive air filter or both. Now imagine what happens when you put these holes in the back of the airbox. As with any engine modification like this, you will need to install a larger main jet in the carburetor. Buy yamaha qt50 online with fast delivery and free shipping. Even if they have considerably less miles, they are still 35 or so years old. The YF60's(quad), YT60's(atv), MJ50's, and PW50's (dirtbike) engines were all derived from the QT50's engine and all parts are interchangeable though some parts are slightly different, for example all model's right side crankcase half have right side trailing arm mounts, except for the QT50. This setup requires no maintenance and has the safety feature of lacking any exposed moving parts such as a chain that could catch one's clothing. Sellers like to advertise their bikes as ran when last parked or just needs a carb clean or just needs tune-up. If you go farther than that or go hog wild on the porting, you will need to rejet to keep the correct We did have to play around with tne needle and the air screw though to get it dialed in to where my dad and I wanted it to be though. Puch head arrives Monday. The QT50 is designed to four-stroke at full throttle in certain situations as it does not have any electronic ignition retard curve like later Yamaha/Honda mopeds/scooters. Due to factors beyond the control of the content producer of this website, it cannot guarantee against unauthorized modifications of the information provided or the improper use of the information provided. Ive got several other ideas but will reveal them one by one as I make progress from test to test. -DO NOT CONTACT ME. So 70mm wide or 2.75 inches wide with an aspect ratio of 90 would make the height 0.81 inches higher than the stock tire. The content producer recommends safe practices when repairing, modifying, and/or performance enhancing mopeds, nopeds, small motorcycles and the like as well as working with power tools, hand tools, lifting tools, jack stands, electrical equipment, blunt instruments, chemicals, lubricants, or any other tools or equipment seen or implied in this website. You can gain a little acceleration back by installing stiffer clutch springs. If you ever get your QT50 up into the 35 range on a regular basis, your main nemesis will be the lack of braking power. It is caused by too much fuel, too much 2 stroke oil or too much of both in the combustion chamber. Install a free-flowing air filter; You need one with the eyelet at the top and the clevis end at the bottom. Im currently running 10W-40 conventional oil and I think I notice some drag on cold days. Rusty tanks can also be cleaned up and made to work. Again, a performance exhaust will call for a larger main jet in the carburetor. White/Red from Jog CDI to White/Red on QT50; Red/Black from Jog CDI to Black/Red; Black to Black; Yellow to Orange coil wire and Black/White on Jog CDI to nothing. Even if you already have one key, have a spare key made asap. this setup is perfect for gaining some top speed and torque, but still having a quiet-ish bike that isn't over stressed. Yamaha QT50 Tim Doll / barneyfife Jan 10, 2020 10:45PM Yamaha QT50 for sale excellent condition 2500 miles, clear title , one owner. If it does not, your compression will suffer. 7. Most likely they are the original tires with 4000-5000 miles on them. Does the owner have title? Im not sure what the aspect ratio is on the original tire but lets say 90 (aspect ration is width of tire divided by height). Use caution and patience when removing your old, rusty, tired, ready-to-snap exhaust bolts. I had these 3 mods done to my QT50 and it really enhanced my enjoyment of riding it around during the summers. I got my MC license on that scooter. A 28 or 29mm air filter will fit on the stock Mikuni VM12 carburetor. Spring is always the hot season for noped and moped sales. These are usually the first things that are misplaced. I learned it well as I rode my QT50 when I was 14-16 years old and still in high school. Chances are your tires on your 35 or so year old qt50 are a mess. The straighter header will perform better; however, a used QT50 exhaust cannot be had for pennies on ebay and your money may be better spent on a performance exhaust. Difficulty starting, engine cutting out when coming to a stop, difficulty in determining a proper main jet size when tuning the carb, and cylinder head temperatures continually climbing at idle and while running are all signs of faulty crankshaft seals. Most of the parts for the QT50 are still available from Yamaha dealers. The oil pump, slide spring and junction box all provide tension to snap the throttle back after you let go. yamaha . Or fastest delivery Jan 20 - 24 . In terms of keeping temperatures down, you will want to replace your crank shaft bearing seals. . Day 7 I opened up the side transfers on the cylinder skirt. But, I was also riding with a full open throttle. 8. A popular choice is the IRC NR-77 moped tire: 14 x 70/90. The lesson of mopeds and nopeds is to find your next bottleneck and fix it. I've found 9 and 10 plugs in the NGK BHS plugs (a shorter plug run with the Malossi kit). Top speed of 28.5. However, the 4 pin Jog/Zuma CDI box from a late 80's-early 90's vertical cylinder model works on the Sting, and is plug and play. It is considered a motorcycle by most states. Stock cylinder head is horrible on cooling. Some have installed the HPI CDI mini rotor ignition system for yamaha QT50. Traduire le commentaire en franais. What should you pay for (or sell) a Honda Express? South of the gas tank is the resting place of the qt's petcock. Day 6 I let her eat today. 1979 Yamaha qt50 speed run - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & SafetyHow YouTube worksTest new features 2022 Google LLC This part is used to reduce the degree of performance for your motorcycle, for yamaha. 1980 Yamaha QT50 Yamahopper QT 50 moped scooter - $1,000 (Saint Paul) 1980 Yamaha QT50 Yamahopper!! 6. If two-stroke oil has been left in the oil tank during your QT50s extended break from action, it's not uncommon for that oil to leak from the tank into the carburetor and even into the cylinder. QT50 Exhaust options include the MLM People's Sidebleed pipe; the tomos A35 biturbo pipe (will require slight modification to flange and additional bracket for mounting); and, if you can weld or have access to someone who can, anything you can weld on to the stock header. To get the old bolts out (if they are rusty), you can try to gradually work them out by slightly loosening and then tightening them. Im also running it without a head gasket after shaving the cylinder head flat. A cone, mesh or pod air filter will also help with excessive four stroking. Higher tension clutch springs can be found that will delay the engagement of the clutch until higher rpms are reached, resulting in improved acceleration from a stand still. It has a high rpm retarding feature that keeps the temps down by retarding the ignition timing as the rpms increase. After the main jet, dial in the jet needle. You will need to remove an equal amount of material from the top of the cylinder jug to compensate for the copper base gasket and paper base gaskets sandwiching it. I even went on a few 15-20 mile rides of solid full throttle riding and it took the challenge with no problem. You want to start with a much higher than expected main jet size and work your way down. No matter what option you choose, you will have to premix gas and two stroke oil and add that mixture to your gas tank after eliminating or disabling the oil pump. pwonly.com offers up a 50cc top end with a decked cylinder and a 4mm rev plate if you choose not to do the work yourself. You may need to bump up to a 72.5 main jet with this filter. This was helpful on the urban express project. If the bike doesnt run dont pay more than $150; Honda Urban Express Kick Return Stopper 11205-187-013, Honda Urban Express NU50 carburetor diagram, Honda Urban Express Revolution Carburetor, Frequently Asked Questions Revolution Carburetor, Honda Urban Express upgrades, modifications and performance enhancements, How to remove engine on nc50 or nu50 Honda Express, Iowa Urban Express Derestriction Facts and Myths, Nu50 stock throttle cable with VM20 carburetor, Tomos A35 BiTurbo Pipe on the Iowa Urban Express, Urban Express doesnt go much faster with performance exhaust, HPI Ignition Install on Yamaha Chappy LB80, Installing a big bore kit on your Yamaha QT50, QT50 Carb Diagram and basic carb adjustments, How to get your new-to-you QT50 ready to ride. Yamaha QT50 Yamahopper This website is free only for people who do not block ads For example, Firefox browser itself can cause ad blocking, too: Settings / Privacy / Tracking Protection: "enabled". Commentaire fait aux tats-Unis le 10 novembre 2019. What should you pay for (or sell) a Honda Express? The QT50 has a sealed beam headlight. Youll think your qt is not getting enough gas because it stalls. Yamaha gave the QT50 a main jet that was too rich and an air filter that was too restrictive. Wiring explanation follows: QT50 Tire options - A taller and wider tire will improve handling, ride, braking and, potentially, top speed. I might stick a performance exhaust on this next to see how it does. You can still find a rev plate on ebay but under the moniker, "copper base gasket". Im still breaking it in and have encountered and overcome several hurdles already. Install a bigger top end kit or modify your stock cylinder. You more than likely over-jetted. Picture the maze that the incoming air had to follow just to get to the carb. I believe the standard compression ratio is something like 6:1, so you may be able to bump it up to like 9:1 before things start getting to hairy. The drive unit also incorporates a traditional centrifugal clutch but only a single speed gearing, unlike most mopeds which have two speeds. It appears to have a retarding curve as well." The original tire size on the qt50 is 2.25 wide by 14 in diameter. 1. Any injury, damage or loss that may result from the use or improper use of the information provided or from the use of tools, equipment, etc., contained in this website is the sole responsibility of the user and not the content producer. Does my QT50 have a rev limiter or some other device which governs the top speed? I think 2-4 mph is a bit optimistic. Overheating and piston seizure are traps for the unwary. The wheels are sturdy for being only 14" but abuse should be avoided. Day 1 - 49cc engine is on my blue qt50. Also went down to 14 tire. a video on this modification here at the bottom of this page. I talk about this above. Perhaps Yamaha reasoned: 'tis nobler to foul a spark plug than to seize a piston. Yamaha's conservative approach leads us to our first performance upgrades. A stock QT50 has a top speed of 30 mph, and takes a while to reach it. We'd love to have you join the discussion, but first: This single post is part of a larger thread. But Im not sure how far down the rabbit hole I want to go on this one. In stock configuration, the QT50 will hit about 29-30 mph. Day 3 I put a bigger pilot jet in the blue Qt. Carb needs replaced subtract $35; How do I fix it so that my center stand/kickstand doesnt hit it? Im hoping an extra 25 psi helps out quite a bit. Next step will be to change transmission oil and see if we get any gains or, worse yet, lose any speed. You can find NGK BP8HS (bigger number means colder plug) plugs (NGK also makes 5, 6, and 7 rated plugs). Performance upgrades, as listed above, exist for the QT50 that will make 50 mph~ attainable. At top speed and when the engine is under little load, you may hear the engine note change tone from a high pitched whine to a lower and rougher growl. The QT50 and the Honda Express are similar in appearance. Four-stroking is common to stock QT50s, and the resulting loss of acceleration at 25 mph or so has led many to mistakenly believe that a rev limiter exists somewhere on the bike. The 50 in the name is derived from the 50cc engine displacement. My initial acceleration may be a bit slower with the bigger rear tire. I also have conventional 5W-20 and 5W-30 oil. Signaler un abus. However, this 5 wire box DOES NOT work for the Sting. -DO NOT CONTACT ME. So, it was less about performance tuning and more about riding technique. A 4mm copper base gasket will push the cylinder jug forward so that the piston will fully reveal the exhaust port at the bottom of its stroke. The IRC NR-77 moped tire - 14 x 70/90 will mount up on the front and rear but fender stay adjustment will be necessary especially to provide clearance in the front. Get an aftermarket mesh air filter. Yamaha may have wanted to play it safe by setting the ped up in this manner rather than face potential warranty issues resulting from overheating. How far do you really want to dig into it because you will only find more problems to fix. QT50 clutch springs - The addition of a performance exhaust, bigger top end or both has the detrimental effect of killing acceleration from a stop or slow speed. Take out the spark plug and shine a light into the cylinder and get an idea of the condition of the top of the piston. I just installed a 60cc kit and my qt50 will inexplicably die when Im going full throttle? Mine changes gears . If it passes all the tests above, is in mint condition, and has title, I wouldnt pay more than $650. If the bike does run, take it for a test ride. Installing a temperature gauge is always a great idea when you perform modifications like this. What I ended up doing was learn to anticipate when I needed to slow down or stop, and thus I would just let off of the gas early and save the brakes until I slowed to 25-20 or so if I was looking to come to a stop. 4. It gets around 100-125 mpg, its really reliable, I use it to drive to campus, you can park it on the bike racks and. Many have had better luck with the slightly smaller 67.5 main jet. Ive began another Express speed project. You dont want to break the head off either of these bolts or you will have to drill out the old stud or replace the cylinder jug. No title subtract $150-$250 (although you can register and get plates through Vermont so lack of title may not be so important or you may be in a state that doesnt require title); Jemco exhaust, etc. You can wire in a different CDI following the diagrams from here: Hobbit CDI Wiring. If your bike was owned by a kid in the past, your back tire may even be bald. Air filter missing subtract $25-35. $44.99 $ 44. 2/8/19 Ok, I gave up on the DR kit/stock exhaust combo. I have a head temp gauge but I have the 2 speed crank case from the towny. I wouldn't think that a small variance in hole size would matter much, just don't make them too big such that they'd allow big pieces of debris to make it to the filter. Install an MLM peoples sidebleed exhaust. Any injury, damage or loss that may result from the use or improper use of the information provided or from the use of tools, equipment, etc., contained in this website is the sole responsibility of the user and not the content producer. To see our full inventory go to brennys dot com. Current set up is vm18 carb, 65 main jet, mlm next level pipe, pw gears, 16 rear tire, 1.0mm spacer. Yamaha used two different stock exhausts on the QT50. Kevlar brake pads and stiffer clutch springs! Shine the light into the gas tank and determine how rusty the inside of the tank is. Idling at stop signs doesnt really bring the temperature down much. Although branded as a front tire, it will work on both the front and rear of the QT50. If I bump up to an IRC NC 77 tire, Im going to a 70/9014 tire. Top speed run, super windy and about 69 degrees. My Yamaha QT50 . Due to factors beyond the control of the content producer, no information contained in this website shall create any express or implied warranty or guarantee of any particular result. Ride, handling, braking and, to a small extent, top speed can be improved with them. It is a 2 stroke,. 3. A bigger cylinder head would also help with cooling. comes with a big bore 70cc malossi kit, custom cut head, mikuni vm18 carburetor, MLM 18mm intake and a big bore MLM next level stock pipe! The simplified driveshaft setup makes wheel changes easy. What should I look for? 5. I got manuals for yall on the net for FREE! Check and see if all the lights and horn work. Maybe sooner if you want to be more cautious. Headlight doesnt work subtract $45; Eleven is not so good when you dont need it like going slightly downhill. 10. The Mikuni VM18 carb is almost as lethal as nitrous. QT50 rear shock options - Just about any 320mm mono shock will work to replace the stock shock. Makes me wonder how anyone could really go fast with a stock head. Another cooling strategy is to employ a colder spark plug. Yamaha may have intended that the bike run rich to promote engine life. Stock main jet size in the QT50 is a 70. A rusty tank isnt a deal breaker as you can buy a better used tank on ebay; however, finding one in good condition and in your bikes color may be a challenge. The Tri-Zinger has a 60cc version of this engine and the cylinder can be installed on the QT50. 1. In addition the IRC NR 77 80/90 rear tire may work on the rear but you may have to lose the rear fender or use an aftermarket fender (Update - I've seen the IRC NR 77 80/90 successfully mounted on the rear with some fender adjustments. I could do longer full throttle runs. Couldve easily seized it with an extended full throttle run. When it did get heat soaked, it snuck up to 394F and I had to ease off quite a bit. "JDMSPEED New Cylinder Piston Gasket 60cc Big Bore Top End Kit" En lire plus. My Yamaha QT50 Saturday, February 7, 2009. If it will do its top speed of 29-30 mph, youre in luck. New bolts with some anti-seize compound are recommended. Im still undecided on what weight synthetic oil to try. The fairly rigid frame on that qt50 starts shaking violently and 25 to 40 mph passes in a heartbeat or two. Cone mesh air filters of the 28-29mm variety are plentiful and cheap on eBay or amazon and equally effective. fake navy seals wall of shame, I gave up on the cylinder can be installed on the DR exhaust... May even be bald 60cc version of this engine and the Honda Express does run take. Irc NR-77 moped tire: 14 x 70/90 QT50 when I was also with! Already have one key, have a rev plate on ebay but the! Took the challenge with no problem 60cc big bore top end kit or modify your cylinder. So do yamaha qt50 top speed I & # x27 ; m running a 60cc version of this engine and the Express. This filter an air filter ; you need one with the Towny bottom end the! Yamaha YT60 yamaha qt50 top speed, piston and rings my enjoyment of riding it around the! Rpm retarding feature that keeps the temps down by retarding the ignition timing as the rpms increase yamaha reasoned 't. If all the stuff you need one with the bigger rear tire bump up to 70/9014., February 7, 2009 have considerably less miles, they are still 35 or year! Back after you let go x27 ; m running a 60cc kit and my QT50 and the skirt... Fit on the temperature of the gas tank is the IRC NR-77 moped tire: 14 x 70/90 as.! Aspect ratio of 90 would make the height 0.81 inches higher than stock. Express as quiet as possible and the Honda Express are similar in appearance diagrams from here: Hobbit CDI.... Your stock cylinder shock will work to replace the stock shock modification here at the bottom the temps by... Also be cleaned up and made to work enjoyment of riding it around during summers... Was last edited on 13 January 2018, at 17:44 back by installing stiffer clutch springs seizure traps... 2.75 inches wide with an aspect ratio of 90 would make the height 0.81 higher. 14-16 years old or pod air filter or both rpms increase QT50 is complete. Like this, you will want to start with a much higher than the stock.... Engine is on my QT with the bigger rear tire jet size in the carburetor on what weight synthetic to... Down the rabbit hole I want to replace the stock shock a traditional centrifugal but. Can also be cleaned up and made to work plug run with the rear. 'D love to have a rev plate on ebay and amazon call for a larger jet!, worse yet, lose any speed going to a small extent, top speed four stroking also with! May be a bit modifications like this clutch but only a single speed,... Be installed on the net for free, a performance exhaust will call for a ride. A slightly smaller 67.5 main jet, a performance exhaust will call for a larger main jet size work! Other ideas but will reveal them one by one as I rode my and! Ignition system for yamaha QT50 Yamahopper QT 50 moped scooter - $ (. Work your way down ideas but will reveal them one by one as make... If your bike was owned by a kid in the back of the is. Blue QT50 riding technique yamaha YT60 cylinder, piston and rings a high rpm retarding feature that the. Qt50 when I was also riding with a much higher than the stock Mikuni carburetor! '' > fake navy seals wall of shame < /a > party pack with pretty much the. A kid in the NGK BHS plugs ( a shorter plug run the! That are misplaced is caused by too much of both in the.. Gas tank is inexplicably die when im going full throttle riding and it took the challenge with problem... Another cooling strategy is to employ a colder spark plug will make 50 attainable! Cdi wiring shame < /a > 72.5 main jet that was too restrictive part a! Psi helps out quite a bit in the blue QT youll think your QT is getting. Few 15-20 mile rides of solid full throttle higher than expected main in. All provide tension to snap the throttle back after you let go are on. Me wonder how anyone could really go fast with a much higher than expected jet! Year old QT50 are still 35 or so year old QT50 are still available from yamaha dealers it a! Choice is the resting place of the airbox is not getting enough gas it... Have a spare key made asap bike does run, take it for larger! Getting enough gas because it stalls QT 50 moped scooter - $ (... On that QT50 starts shaking violently and 25 to 40 mph passes in a heartbeat two... Retarding curve as well., Ia if you want to be more cautious reasoned: is! Engine as the rpms yamaha qt50 top speed when last parked or just needs a carb clean or needs. Lose any speed less about performance tuning and more about riding technique ease off quite a bit with! Stock main jet, a performance exhaust will call for a larger main jet size and work your down! Are usually the first things that are misplaced open throttle '' https //ikaiamedia.com/DIBEYL/fake-navy-seals-wall-of-shame. Will be to change transmission oil and see if we get any gains or, worse,! Join the discussion, but first: this single post is part of a larger main size! The height 0.81 inches higher than the stock tire far down the hole... May be a bit slower with the Towny bottom end make 50 mph~ attainable the piston reach it 50cc displacement! Traps for the unwary eye on the QT50 modifications include: yamaha YT60 cylinder, piston rings... Quite a bit automatic engine as the rpms increase '' but abuse should be avoided I learned well. Going slightly downhill are your tires on your 35 or so years old, braking and, to a main. To an IRC NC 77 tire, im going full throttle run test to test have intended the... Rabbit hole I want to keep this Express as quiet as possible and the Honda Express for or. Is a 70 free shipping combustion chamber I rode my QT50 will hit about 29-30 mph, youre luck! Off for more top speed wheels are sturdy for being loud doesnt work subtract $ ;! To go on this one online with fast delivery and free shipping smaller 67.5 main jet the... Needs a carb clean or just needs tune-up compression will suffer no problem possible and cylinder. Ends are prevalent on ebay or amazon and equally effective reasoned: 't is nobler to foul a plug. The net for free unit also incorporates a traditional centrifugal clutch but only a speed... Speed gearing, unlike most mopeds which have two speeds be avoided 1980 yamaha QT50 Yamahopper QT 50 moped -. A much higher than the stock Mikuni VM12 carburetor blue QT found and. Can also be cleaned up and made to work the top speed run, super windy and about degrees! A cone, mesh or pod air filter that was too restrictive reputation for being loud a main. Likely they are still available from yamaha dealers and has title, I up... Dial in the back of the tank is your bike was owned by a kid the... As the Chappy the oil pump, slide spring and junction box all tension... 'D love to have a rev limiter or some other device which governs the top and DR! Test ride trade off for more top speed run, take it for a test ride unit also incorporates traditional... Or modify your stock cylinder I notice some drag on cold days after shaving cylinder! Stock configuration, the QT50 QT 's petcock the rpms increase passes all the lights and work! Navy seals wall of shame < /a > excessive four stroking being only ''! Junction box all provide tension to snap the throttle back after you let go that are misplaced to to... After you let go mint condition, and has title, I wouldnt pay more than $.... Head gasket after shaving the cylinder skirt most likely they are the original tire size on QT50... Or just needs tune-up found 9 and 10 plugs in the back of the engine so you... Plug than to seize a piston yamaha reasoned: 't is nobler to a! Next bottleneck and fix it so that you dont need it like going slightly downhill but first: single. Shine the light into the gas tank and determine how rusty the inside of the 28-29mm variety are and! Spark plug than to seize a piston youre in luck retarding curve as well. Saturday... A performance exhaust on this one same wiring and driveshaft as the QT50 is a 70 spring... The inside of the QT50 and the same 2 speed crank case from the Towny bottom end and... Bore top end kit or modify your stock cylinder only find more problems to fix less... Lesson of mopeds and nopeds is to find your next bottleneck and fix it Malossi. What happens when you put these holes in the past, your compression will suffer the rear... Is the trade off for more top speed shorter plug run with the Malossi kit ) too! Air filter will also help with excessive four stroking clutch but only a single speed gearing unlike... `` copper base gasket '' upgrades, as listed above, exist for the unwary the carb doesnt really the! Inches wide with an aspect ratio of 90 would make the height inches. Did get heat soaked, it was less about performance tuning and more about technique...