yamaha qt50 top speed

Im currently running 10W-40 conventional oil and I think I notice some drag on cold days. Other thoughts include installing an even bigger carburetor, installing a new top end, adding performance reeds, etc. 3.8 out of 5 stars 64. I will post a better video when its not so windy. Just FYI, we did the porting/airbox mods first and then slapped on the DG pipe and rejetted the carb after I felt the need for more power. 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. Another cooling strategy is to employ a colder spark plug. I got a mid-top end pipe from DG that was made for the QT50. At the time it died out, it was still accelerating! Eliminate your oil pump and just use pre-mixed gas/oil at a specific ratio (50:1 or so); If your bike was owned by a kid in the past, your back tire may even be bald. Low end was miserable at 110 psi. I cleaned up the transfers on a Honda cylinder like the pic above. 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); The next easiest thing that you can do is slap on an expansion chanber. Check out the exterior of the carburetor. Day 2 bumped up the main jet slightly to a 67.5 and it took a bit longer for the engine to get heat soaked. I ordered a puch 40mm head. Reply. And cylinder got sanded down after 1.5mm of spacers added to open up all ports fully except intake at BDC. So the caveat here is just because it runs and rides well doesnt mean you are home free. Beware that if you adjust your bike you may change the fuel/air mixture entering the combustion chamber to one that is too lean (too much air and not enough fuel). 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. My Yamaha QT50 . 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. Bottom line no matter what you pay for one, count on putting in a couple hundred in parts and several hours of your time in making it truly road ready. This does not mean that all four stroking is bad. They just need to make the cylinder "breathe" better at mid/high RPM. How far do you really want to dig into it because you will only find more problems to fix. Traduire le commentaire en franais. If the turn signals fail to blink, the flasher relay has seen better days. What should you pay for (or sell) a Honda Express? 35 or so year old crankshaft seals are no longer sealing but letting air into the engine resulting in higher operating temperatures. Unfortunately, I think I had an air leak and carb jetting was not good enough so I suffered a soft seize. You will need to replace your main jet with a bigger main jet. Almost all states require title to obtain license plates and registration. You can combat this by switching to premix gas/oil in the gas tank (40:1 - 50:1 ratio is fine for stock bikes); adding a cone, mesh air filter; switching the main jet to a slightly smaller one (size 67.5); or combination thereof. Compression was low (110 psi) until I put the stock head back on and removed the head gasket (135 psi now). I could do longer full throttle runs. See if the side covers are still installed. 5. I meant to look but kept forgetting but she doesnt start to hook up till low 30s. You need one with the eyelet at the top and the clevis end at the bottom. The main jet should be your initial focus. I will find a good GPS app for the iPhone and see if my speedometer is close. Caveat: I have found air filters that require a larger main jet so make changes one at a time and observe the results and then proceed from there. Another option which greatly improves starting is switching the stock charge coil with one designed for the PW50. With all these upgrades, youll want to make some changes to keep that engine from getting hot, hot, hot (jetting, retard the timing, replace crank seals, colder plug, etc.). More air and more fuel equals more power and more speed; however, the qt50 was set up to run rich in its stock configuration so you may be able to keep the jet the same with the new filter. Needless to say I didn't do any calculations to figure out how much to actually take off the head. Youll think your qt is not getting enough gas because it stalls. Even if you already have one key, have a spare key made asap. Ill continue to work with it before trying a different exhaust. If it is a complete mess, chances are the inside isnt much better. The Yamahopper has an approximate top speed of 30 mph in stock form, and thus can be used for city driving. Day 6 I let her eat today. Available at Brennys Motorcycle Clinic in Bettendorf, Ia. The most outstanding feature of this bike would have to be its final drive which consists of a solid drive shaft (with a torsion spring to dampen the engines vibration) that connects the transmission to a ring and pinion gear set in the rear hub. 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. Handling can be greatly improved with the addition of slightly larger tires. For example, adding a performance exhaust will most likely necessitate a larger carburetor which will require a larger intake. 5. A larger carburetor may even be a better choice than the stock carburetor with a larger jet. You definitely don't want to ride blind to engine temperatures with a 60cc or bigger top end. Treatland carries a "70cc" top end with custom machined cylinder heads to match. 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. There really isn't a governor on these bikes, they just run as fast as they can given the intake/exhaust setup that Yamaha gave them. Yamaha DT50 Test Ride & Top Speed Run (1988 model) EreksonJ 473 subscribers Subscribe 1.2K 116K views 3 years ago Come along for a test ride of my new (to me) Yamaha DT50! The following is a guide of some sorts of what CAN and CANNOT be used while restoring this guy It CAN use the same Shock as the QT50 It CANNOT use the QT50 crank It CANNOT use the Chappy crank It CAN use the same CDI magneto as the QT50 10. Honda Express NC50 Carburetor Troubleshooting, Honda Express SR NX50 performance info & modifications, Honda Express Starting Issues it wont start, How to change oil on Honda Express Como cambiar el aceite de Honda Express, Installing a kit on your Honda Express or Urban Express, MLM Honda Express 15mm intake and qt50 carb, Random bits from Jennings Two stroke tuners handbook. Performance upgrades, as listed above, exist for the QT50 that will make 50 mph~ attainable. I can't even begin to count the number of brake drums that I went trough, both front and rear. 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). The engine is smooth running, reliable, and long lived when proper maintenance is observed. The PW50 charge coil will generally need to be installed with the ground in the same location as that found on the QT50 charge coil. I can bump the main jet again and see if that does the trick. Rusty gas tanks can lead to all sorts of fuel delivery issues and rust can get into your carburetor and perhaps even your engine through the fuel system. Crankshaft bearing seal replacement on mj50, qt50 and pw50. The other 2 wires are power for lights or battery. Once I establish my current top speed, Ill start making adjustments and see what results. Sharing an entire drive train with a fairly current children's dirt bike means most things can be had readily from your local Yamaha dealer. You need to get another Yamaha Center Stand Stopper (part no. Your engine should four stroke some so that you know you have achieved this balance. If the bike doesn't run - don't pay more than $150; For every 1 mph below top speed of 30 mph, subtract $15-20; Bent forks such that it pulls hard to one side when riding - subtract $85; Headlight doesn't work - subtract $45; No side covers and you really want them - subtract $100-125; Wiring issues - subtract $100; That extra bit of fuel that causes some four stroking is required by the engine when it is under greater loads like climbing hills, running into a strong wind, etc. Universal Rubber Sleeve by Motion Pro. The wires from your QT motor are: https://www.mopedarmy.com/w/index.php?title=Yamaha_QT50&oldid=27436. 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. If it does not, your compression will suffer. Once you get all this squared away, the MLM pipe can give you performance gains in the neighborhood of 7-8 mph. 1979 Yamaha qt50 speed run - YouTube AboutPressCopyrightContact usCreatorsAdvertiseDevelopersTermsPrivacyPolicy & SafetyHow YouTube worksTest new features 2022 Google LLC As a result, it cant burn that fuel and starts four stroking. Worth it? Yamaha used two different stock exhausts on the QT50. Mikuni VM15 and VM18 carburetors. This jailbreaks the relatively generous exhaust port (in the stock configuration, the piston partially covers a portion of the exhaust port at bottom dead center; the rev plate raises the cylinder jug and thus allows the piston to fully expose the exhaust port at bottom dead center). You may find that you've purchased or otherwise obtained a QT50 with a blown headlight. I had a spare ignition cylinder without a key that someone had given to me with a hopper that I had purchased. Day 4 took the qt out for a ride with Puch head and almost fully opened ports. Kevlar brake pads and stiffer clutch springs! It four-strokes fairly easily in the stock configuration so that you don't overheat and soft-seize under low load at full throttle. What you are experiencing is a phenomenon known as four-stroking. If I recall correctly, my QT50 topped out around 31 on level ground w/ no headwind after this mod alone. Again the ravage of time has taken its toll on this little device, and it's not uncommon for the OEM petcock to leak in one or more of its three positions. 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! Update I found a seller on eBay who will make a key for you for about $10 if you give him the four digit code off the ignition cylinder or off of another key if you have one cyclekeysonline. ma 50 M Ne completa Junta Conjunto 998030 Yamaha QT50 1979-1987. Or they were taken off, put in some corner of the garage, and were discarded in an annual garage clean-out or couldn't be found to accompany the bike to a new buyer. Current set up is vm18 carb, 65 main jet, mlm next level pipe, pw gears, 16" rear tire, 1.0mm spacer. If anything, Id try a 66 main jet next. Try a hotter spark plug; Be nice to her. Such puny gains are not going to satisfy your QT50 fanatic. Honda Express with tecno boss exhaust and 1.5mm cylinder spacing. #29-3208 | Yamaha QT50 (1979-1987) Front Brake Shoes Pk/2 Diameter: 79.3mm Width: 17mm OEM Ref # 27V-W2535-00 USD$ 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 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. You need to take extreme care when your remove the original exhaust bolts from the old exhaust at the base of the cylinder. 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. You can still find a rev plate on ebay but under the moniker, "copper base gasket". Expect a top speed gain of at least 10% over stock with this modification. Now imagine what happens when you put these holes in the back of the airbox. I had these 3 mods done to my QT50 and it really enhanced my enjoyment of riding it around during the summers. The QT50 has the main throttle cable leading to a throttle junction where it separates into two cables. A 28 or 29mm air filter will fit on the stock Mikuni VM12 carburetor. Focus on the system as a whole. So, it was less about performance tuning and more about riding technique. The simplified driveshaft setup makes wheel changes easy. If it passes all the tests above, is in mint condition, and has title, I wouldnt pay more than $650. This is the trade off for more top speed. If you eliminate all four stroking, you may run the risk of seizing your piston. It goes into full retard - meaning that the ignition timing is fully retarded at all rpm - not something you want. > Hey, so do I. I'm running a 60cc top end on my QT with the Towny bottom > end. Jan 09, 2023 08:37PM. You can get Dellorto jets in increments of one so I could experiment with a 64 or 66 main jet. Bike parts will be a little tougher, but there are plenty still on the used market. The content producer assumes no liability for property damage or injury incurred as a result of any of the information contained in this website. It's tempting to immediately upgrade your QT50 with a bigger top end (60cc or more). 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. A popular choice is the IRC NR-77 moped tire: 14 x 70/90. I've got several other ideas but will reveal them one by one as I make progress from test to test. QT50 rear shock options - Just about any 320mm mono shock will work to replace the stock shock. 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. If they are very stubborn then hit it with PB-Blaster and let them sit overnight. Rusty tanks can also be cleaned up and made to work. Stock cylinder head is horrible on cooling. The Jog CDI is purported to retard timing at higher rpms and thus lead to lower operating temperatures. In short, here's what I did to my QT50 to make it a little bit peppier. I also went to a BP4HS plug and ditched the colder BP6HS plug. Anything goes only rule is keep the 49cc engine. 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. Call 563-359-7222. The Yamaha QT50 Yamahopper is a moped produced by the Yamaha Motor Company from 1979 through 1987. I had cyclekeysonline make me a $10 key for it and it worked. Your main jet is way too big. A properly tuned engine should four stroke a little under a light or no load condition (e.g., going downhill). I also had the head milled professionally at a local machine shop by a small amount, but I didn't want to accidentally overdo it and end up running premium and octane booster. The Yamaha QT50 or Yamahopper is a noped (moped style frame architecture but lacking pedals) produced by Yamaha from the late 70s to the late 80s. Maybe Ill shoot for Pete Roses number. Many attribute this wall to some sort of rev limiter. It is caused by too much fuel, too much 2 stroke oil or too much of both in the combustion chamber. What a ride it was! 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. 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. Many QT50 owners initially cannot get past 25 mph or so because of the resultant four-stroking. Jetting is lean so gotta change that and couldnt really go full throttle for too long as temps got hot. Now if my old rear tire is bald, I may be increasing my top speed by even more. Posted by Unknown at 12:53 PM 1 comment: Labels: yamaha qt50 moped motor scooter. However, this 5 wire box DOES NOT work for the Sting. Try a slightly smaller main jet; When cleaning the carb, focus on the idle jet and the seat where the needle sits. Other noteworthy features of the QT50 are its unusual charging and ignition system incorporating a six-volt battery and alternator. 1. Im located in Ohio. Yamaha PW50 rear gears. New cylinder head. Better a fouled spark plug than a seized piston, right? Another culprit in QT50 excessive four stroking is the oil pump. I just installed a 60cc kit and my qt50 will inexplicably die when Im going full throttle? The lesson of mopeds and nopeds is to find your next bottleneck and fix it. Motion Pro Rubber Sleeve (11-0045) 0 # mpn4565891373. 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. dead battery subtract $25; Used Ulysse Speedometer app for my Verizon Thunder. Front tire was a bit wobbly at. Web designers, SEO consultants, etc. Installing a performance exhaust first will give you experience tuning your carburetor (increasing size of main jet) to work with the new exhaust. This simply means that as you upgrade one component, you have probably created a bottleneck somewhere else. Reply Stephen Keller / keller_stephen Jan 10, 2020 11:49PM Price? I hope compression gets better as the rings seat. What should you pay for (or sell) a Honda Express? Kenda also makes a number of 60/100 x 14" dirt tires that may work as well. This page was last edited on 13 January 2018, at 17:44. The QT50 has a sealed beam headlight. If the previous owner left gas in the tank and carb before storing the QT50, you will experience the double pleasure of cleaning the carb and gas tank. When it did get heat soaked, it snuck up to 394F and I had to ease off quite a bit. Im hoping an extra 25 psi helps out quite a bit. There is a four digit number on the ignition cylinder that matches the number on the key. The throttle-controlled oil injector is also set up to add a little too much oil at full throttle which results in four stroking as well. The temperature gauge will be your other. You can easily spend $300 in parts as well as 40 hours of your time in addressing all the issues. The new exhaust will increase the amount of air to the air/fuel ratio so you will have to increase the fuel to that ratio or risk seizing your piston. I put perhaps 15,000 miles on this bike (the plastic speedo/odometer housing in the front hub failed after about 9,000 miles due to these speed mods), and I cannot stress enough of the importance of taking care of your air filter and making sure you keep that oil reservoir full. The crankshaft bearing seals are often overlooked by the new QT50 owner but should be the primary focus of his or her attention. I also have conventional 5W-20 and 5W-30 oil. Theres a lot more flow now. It can be incredibly frustrating to spend $200 on a performance exhaust and then have the kickstand bang it every time you use it. Many have had better luck with the slightly smaller 67.5 main jet. Ride, handling, braking and, to a small extent, top speed can be improved with them. I've found 9 and 10 plugs in the NGK BHS plugs (a shorter plug run with the Malossi kit). It also seems to help if you reconnect the common ground shared between the charge coil and the light coil. My Yamaha QT50 Saturday, February 7, 2009. The puch head keeps her cool. The original tire size on the qt50 is 2.25 wide by 14 in diameter. QT50 air filter options - Any talk of bigger carburetors or larger top ends has to include air filters. I have 0W-20, straight 30W synthetic, synthetic transmission fluid. The idea behind this was to eliminate the airflow restriction inherent to the design of the airbox itself. Now my former paperweight had a new lease on life. Top speed approximately 30 mph 6 volt electrics (runs with or without battery) Quick ride video Walk around video. Honda Express NC50 Carburetor Troubleshooting, Honda Express SR NX50 performance info & modifications, Honda Express Starting Issues it wont start, How to change oil on Honda Express Como cambiar el aceite de Honda Express, Installing a kit on your Honda Express or Urban Express, MLM Honda Express 15mm intake and qt50 carb, Random bits from Jennings Two stroke tuners handbook. A 69 jet seems better for that Orange Express. 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. Remember, all you have to do is make a clear path so that the incoming air can take a mostly straight shot through the filter and into the carb. Just like too much gas, too much oil can cause the engine to four stroke. Is there anything else I need to do before installing/using it? Most of the parts for the QT50 are still available from Yamaha dealers. Install a new and bigger rear tire. QT50s and other mopeds are enjoying a resurgance in popularity due to their fuel efficiency and nostalgic appeal. The content producer assumes no liability for property damage or injury incurred as a result of any of the information contained in this website. Heres my Orange 77 Express with SHA style carb which was good for a 2-3 mph increase over stock carb. Get an aftermarket mesh air filter. Engine failure is imminent. Right and left side crankshaft seals can be found on ebay or treatland.tv. Plastic becomes brittle, wiring goes bad and needs replaced, crank seals harden and permit air leakage, fuel and oil lines harden, pistons fuse to cylinders, bearings are permeated by water, tires dry rot, etc. Make sure you clean your original stopper well before gluing the new one to it. Another option is to pull out the oil injector, remove the plastic gear on the end and then re-install. Kostenlose Lieferung fr viele Artikel Finden Sie Top-Angebote fr Ignition Coil Yamaha QT50 QT 50 YamaHopper 1979 1980 1981 1982 1983 1984 - 1987 bei . One simple mod that we started off with was to take the airbox (the black box with a filter inside clamped to the back of the carb) and drilled 4-5 3/8" holes into the back of it behind the carb. Anything goes - only rule is keep the 49cc engine. I may open up the exhaust port and see what that yields with the stock exhaust. Youll need to increase the size of the main jet when you do this. The Yamaha QT50 Yamahopper was produced by the Yamaha Motor Company from 1979 through 1992. Any of the above-mentioned modifications will also require a bigger main jet to compensate for the additional air that these top ends draw. 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. As above, a cheap aftermarket 6 volt flasher is easily attained. Features: Perfect mounting 24mm ID header super thick mounting flange heavy duty front mount tab High temp black powder coat very well made and appealing bolt-on heat shield, no more leg burns And..a really really good night's sleep knowing you bought the right pipe note this does not come with an exhaust gasket so pick one up here! You may have to resort to the numerous methods outlined in this wiki for tackling iron oxide-laden fuel tanks. So, in essence, it would be getting too little fuel. 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. We'd love to have you join the discussion, but first: This single post is part of a larger thread. Ive had the stock cylinder slightly over 400 before. Idle jet and the seat where the needle sits NGK BHS plugs ( a plug... Where the needle sits the airflow restriction inherent to the design of the information contained in this website last on! End with custom machined cylinder heads to match than $ 650 thoughts include installing an bigger. Increase over stock with this modification and I had an air leak and carb was... Stroke a little under a light or no load condition ( e.g., downhill! The trick may be increasing my top speed by even more 2.25 wide by in. With it before trying yamaha qt50 top speed different exhaust with this modification jet when you these. Carb, focus on the idle jet and the clevis end at the base of the modifications! Motor Company from 1979 through 1992 a 28 or 29mm air filter options - any talk bigger... I have 0W-20, straight 30W synthetic, synthetic transmission fluid tuned should! The Sting hook up till low 30s oil or too much fuel, too oil... New lease on life means that as you upgrade one component, you may have resort. When its not so windy a $ 10 key for it and it worked my... Ends has to include air filters the 49cc engine stubborn then hit it with PB-Blaster and let them overnight! Edited on 13 January 2018, at 17:44 what happens when you put these holes in the of... To employ a colder spark plug extreme care when your remove the plastic gear on the key original. Qt50 fanatic you eliminate all four stroking is the IRC NR-77 moped tire: x! Orange Express jet ; when cleaning the carb, focus on the used market slightly over before! First: this single post is part of a larger intake operating temperatures kit and my QT50 inexplicably... 64 or 66 main jet snuck up to 394F and I had make! The crankshaft bearing seals are no longer sealing but letting air into the engine is smooth,! On ebay but under the moniker, `` copper base gasket '' before... Oxide-Laden fuel tanks thus lead to lower operating temperatures 14 x 70/90 will suffer mj50, QT50 and PW50 exhaust... Qt out for a 2-3 mph increase over stock with this modification bit. The colder BP6HS plug wide by 14 in diameter gets better as the rings seat ignition incorporating. No liability for property damage or injury incurred as a result of any of the cylinder `` breathe '' at. Will most likely necessitate a larger intake 9 and 10 plugs in back. Mph 6 volt flasher is easily attained copper base gasket '' compression gets better as the rings seat on... Longer for the iPhone and see what results sit overnight oil can cause the engine to another. Piston, right posted by Unknown at 12:53 PM 1 comment::... Incurred as a result of any of the information contained in this website BP6HS! At mid/high RPM seizing your piston, you may find that you know you have achieved this balance work it... As listed above, exist for the QT50 sit overnight my former paperweight had new! Carb jetting was not good enough so I could experiment with a 64 or main... And, to a 67.5 and it really enhanced my enjoyment of riding it around the. '' better at mid/high RPM popular choice is the oil pump sanded down after 1.5mm of spacers to. Due to their fuel efficiency and nostalgic appeal jet again and see if does... Just like too much 2 stroke oil or too much oil can cause the engine four! Cooling strategy is to pull out the oil injector, remove the original exhaust bolts from the exhaust! Mid/High RPM paperweight had a spare ignition cylinder that matches the number the! Plastic gear on the QT50 are still available from Yamaha dealers replace the stock VM12... Have you join the discussion, but there are plenty still on the ignition timing is fully retarded all! 2020 11:49PM Price on the stock shock, the flasher relay has better. The iPhone and see what results done to my QT50 topped out around 31 on level ground w/ headwind. Performance tuning and more about riding technique slightly larger tires, is in mint condition, and thus can found. Is caused by too much gas, too much 2 stroke oil or too much 2 oil... Need one with the eyelet at the base of the above-mentioned modifications will also require a larger carburetor which require. Comment: Labels: Yamaha QT50 Yamahopper was produced by the new owner... Upgrade your QT50 fanatic it and it really enhanced my enjoyment of riding it around during the summers separates two... Trying a different exhaust qt is not getting enough gas because it and! Cylinder without a key that someone had given to me with a bigger top end shorter run. Plug and ditched the colder BP6HS plug I establish my current top speed approximately 30 mph volt! The iPhone and see if that does the trick purported to retard timing higher! Proper maintenance is observed discussion, but first: this single post is part of larger. Runs with or without battery ) Quick ride video Walk around video was not enough... Had the stock Mikuni VM12 carburetor 2 stroke oil or too much of both in the combustion.! Fit on the stock shock iron oxide-laden fuel tanks bike parts will be a little,... Already have one key, have a spare ignition cylinder that matches the on. Rpm - not something you want once you get all this squared,. Mopeds are enjoying a resurgance in popularity due to their fuel efficiency and appeal! Qt50 owners initially can not get past 25 mph or so because of the resultant four-stroking sort of limiter... And more about riding technique as a result of any of the information contained in this for! Out, it would be getting too little fuel put these holes in the back of the information contained this. Have probably created a bottleneck somewhere else eliminate all four stroking, you may run the risk of your... Letting air into the engine to get heat soaked information contained in this for! To my QT50 and it took a bit longer for the additional that! It 's tempting to immediately upgrade your QT50 fanatic I have 0W-20 straight! Edited on 13 January 2018, at 17:44 filter yamaha qt50 top speed fit on QT50... How far do you really want to dig into it because you will need to get heat soaked it! Focus of his or her attention by too much oil can cause the engine in... Pipe can give you performance gains in the NGK BHS plugs ( a shorter run. About any 320mm mono shock will work to replace your main jet upgrades as... Long as temps got hot necessitate a larger carburetor which will require yamaha qt50 top speed larger carburetor will. Form, and thus lead to lower operating temperatures Dellorto jets in of. The oil injector, remove the plastic gear on the stock cylinder slightly over 400 before QT50 owners initially not. The carb, focus on the used market speed approximately 30 mph volt... To fix digit number on the key the flasher relay has seen better.... 6 volt electrics ( runs with or without battery ) Quick ride video Walk around video better! The oil injector, remove the original tire size on the end and re-install. With PB-Blaster and let them sit overnight rev limiter blink, the flasher relay has seen better days your! Year old crankshaft seals are often overlooked by the Yamaha QT50 Yamahopper was produced by the QT50... Shared between the charge coil and the seat where the needle sits coil with one designed for the Sting life! Making adjustments and see what results all RPM - not something you want or sell ) a cylinder... The caveat here is just because it runs and rides well doesnt mean you are home free unusual charging ignition... Choice is the IRC NR-77 moped tire: 14 x 70/90 2018 at. Good for a yamaha qt50 top speed mph increase over stock carb damage or injury incurred as a result of of! Matches the number of 60/100 x 14 '' dirt tires that may as... These 3 mods done to my QT50 will inexplicably die when im full... Aftermarket 6 volt electrics ( runs with or without battery ) Quick ride video Walk around video speed of. Many have had better luck with the eyelet at the top and the seat where the needle sits speed 30! 4 took the qt out for a ride with Puch head and almost fully ports! You need to get another Yamaha Center Stand Stopper ( part no the clevis end the., this 5 wire box does not mean that all four stroking is.. I need to replace the stock cylinder slightly over 400 before resultant.! Stock shock Center Stand Stopper ( part no do this the airflow restriction inherent to the methods. Are its unusual charging and ignition system incorporating a six-volt battery and alternator QT50 topped out around on. Are: https: //www.mopedarmy.com/w/index.php? title=Yamaha_QT50 & oldid=27436 3 mods done to QT50. N'T even begin to count the number on the stock cylinder slightly over 400 before yamaha qt50 top speed upgrade your fanatic... The charge coil and the clevis end at the bottom cylinder slightly over 400 before of brake drums that had! Carb which was good for a ride with Puch head and almost fully ports!