yamaha qt50 top speed

Of course any top end gains will come at the expense of low end loss and right now 0-15mph aint great. Youll think your qt is not getting enough gas because it stalls. I never ran into overheating problems, nor did I ever have a mechanical breakdown because I kept up on its maintenence. 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. clutch yamaha qt50 hand yamaha pw50 yamaha mt 15 singapore pee wee yamaha pw50 yamaha qt50 wiring diagram yamaha qt50 top speed. This cut down on the brake bill dramatically. 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. The VM18 will require MLM's intake designed for the VM18. Thanks to this handy calculator, I see that my speed at 30 mph with the old rear tire should now be 31.53 mph. 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. I have 0W-20, straight 30W synthetic, synthetic transmission fluid. My bike ran on the rich side at high rpm from the dealership, so I didn't have to go the next larger size on the main jet after the mild airbox/porting mods we performed. Top speed approximately 30 mph 6 volt electrics (runs with or without battery) Quick ride video Walk around video. Took a ride with current setup as listed above. Web designers, SEO consultants, etc. I hope compression gets better as the rings seat. Home. #3 billtrout , Jun 20, 2013 #4 billtrout Adventurer Joined: Aug 15, 2012 Oddometer: 10 Location: Jersey I rode one for a couple of years, it was my first rode legal Bike. I can bump the main jet again and see if that does the trick. 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 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. Stock main jet size in the QT50 is a 70. I even went on a few 15-20 mile rides of solid full throttle riding and it took the challenge with no problem. If you eliminate all four stroking, you may run the risk of seizing your piston. Ill continue this list over time because there is a lot you can do to go faster on a qt50. 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. What follows are my attempts to obtain the best performance from the stock 49cc Yamaha qt50 engine. My top speed now is somewhere around 28 mph. I solved it by going from a 102.5 jet to an 87 and finally to an 85 main jet. Ill test it on the urban and if it helps then Ill do the same to the qt cylinder. 3.8 out of 5 stars 64. 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. Several methods are outlined here at mopedarmy.com. 1. A bigger carburetor will provide better cooling for your larger top end. Jetting is lean so gotta change that and couldnt really go full throttle for too long as temps got hot. If it does not, your compression will suffer. For your viewing pleasure, here it is: I put a Tecno Boss pipe on to this Express and did some modifications to the cylinder and here we are. Call 563-359-7222. Mine changes gears . Yamaha MJ50 Towny two-speed crankcase and right-side swingarm. Low end was miserable at 110 psi. 9. #4 Stock Configuration and Basic Performance Upgrades, https://www.mopedarmy.com/w/index.php?title=QT50_performance&oldid=24781. The Yamahopper has an approximate top speed of 30 mph in stock form, and thus can be used for city driving. 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. YES! If your bike was owned by a kid in the past, your back tire may even be bald. 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. Trail Tech makes a temperature gauge which has a copper washer that replaces your current spark plug washer. Manufactured. Heres a nice picture of the stock tire vs. the IRC tire. Because I opened up the reed block slightly, a 2.5 increase in jet size is significant. Las mejores ofertas para Ne completa Junta Conjunto 998030 Yamaha QT50 (ma 50 M) 1979-1987 estn en Compara precios y caractersticas de productos nuevos y usados Muchos artculos con envo gratis iptvza.com. QT50 rear shock options - Just about any 320mm mono shock will work to replace the stock shock. You can get Dellorto jets in increments of one so I could experiment with a 64 or 66 main jet. 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. 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. 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, using a key other than the Yamahopper one. Youd seize before you got to 40. 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. Look how wrong you can be. A 69 jet seems better for that Orange Express. Subscribe to: Posts (Atom) This part is used to reduce the degree of performance for your motorcycle, for yamaha. I just bought an MLM peoples sidebleed pipe for my QT50/MJ50. Your qt50 should start up easy, run smooth and have a top speed around 30mph in its stock configuration. $650 in Ohio may be the same as $900 in California or New York. Add a 3-4mm copper/aluminum spacer to the base of the cylinder and deck the cylinder the same amount. New cylinder head. It's simple, maintenance-free shaft-drive contained in the single-sided swingarm eliminates chain maintenance, safety and wear concerns as well as weather wear factors and contributes to the durability and ease of use of these tiny motorbikes. 8/6/2018 So I kind of lost track of this thread and thought Id pick it up again. 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. If I bump up to an IRC NC 77 tire, Im going to a 70/9014 tire. FREE delivery Jan 25 - 31 . It has a high rpm retarding feature that keeps the temps down by retarding the ignition timing as the rpms increase. Yamaha Yamahopper qt50 top speed run, hang on! 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! 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. This is one reason why these bikes top out just above 25mph from the factory! Replacement of its gasket can be undertaken or a cheap aftermarket fuel cock can be had with little trouble. 5. Rusty tanks can also be cleaned up and made to work. Ron Peek / yamahauler. Does my QT50 have a rev limiter or some other device which governs the top speed? On a large ride, I was able to keep up with the Puch's and Carabela's. Waiting on puch head to arrive. You can also find a woodruff key for PW50s used to advance the timing but you should be able to install it in reverse to retard the timing. Even if they have considerably less miles, they are still 35 or so years old. You can still find a rev plate on ebay but under the moniker, "copper base gasket". No side covers and you really want them subtract $100-125; Youll need to increase the size of the main jet when you do this. (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!!) Again, a performance exhaust will call for a larger main jet in the carburetor. Focus on the system as a whole. I go over some pretty simple cylinder modifications to get more speed.spacers - https://www.treatland.tv/SearchResults.asp?Search=honda+metal+spacer+basespac. Generally, if you let off the throttle a little bit, the high pitched whine will return. 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. I'll make videos of each top speed run and post them here. Yamaha's conservative approach leads us to our first performance upgrades. Didnt have any trouble until I climbed 3 hills in a row and then we hit 395F. Im also running it without a head gasket after shaving the cylinder head flat. 50 mph. -DO NOT CONTACT ME. 4. A slightly larger 32mm will probably fit as well and many options exist as that is the typical size for PHBG carburetors. Im still breaking it in and have encountered and overcome several hurdles already. Day 3 I put a bigger pilot jet in the blue Qt. Many mistake the low, rough growl as a result of a rev limiter residing in the CDI unit or perhaps elsewhere. My Yamaha QT50 Saturday, February 7, 2009. Many have had better luck with the slightly smaller 67.5 main jet. Chances are your tires on your 35 or so year old qt50 are a mess. Current set up is vm18 carb, 65 main jet, mlm next level pipe, pw gears, 16" rear tire, 1.0mm spacer. Heres a nice picture of the stock tire vs. the IRC tire. In its factory form, the Yamaha QT50 should reach a top speed of around 28-30 mph. I had these 3 mods done to my QT50 and it really enhanced my enjoyment of riding it around during the summers. I can probably jet higher after getting the piston to clear the ports. Remplacement pour Yamaha QT50 1979-1987 ; . I had a spare ignition cylinder without a key that someone had given to me with a hopper that I had purchased. I talk about this above. Ive never tried this but I imagine you can take that 4 digit number to a Yamaha dealer and they might be able to make you a new key. dead battery subtract $25; If you are eventually planning on a bigger top end, go with the VM18. A 28 or 29mm air filter will fit on the stock Mikuni VM12 carburetor. Hey, so do I. I'm running a 60cc top end on my QT with the Towny bottom end. I meant to look but kept forgetting but she doesnt start to hook up till low 30s. I was bummin' that my 83 QT50 would bog out at 25mph. This is not a moped since it doesnt have pedals. Alternatively, add-ons / plugins in browsers, not just only AdBlock, but also others similar, too. It goes into full retard - meaning that the ignition timing is fully retarded at all rpm - not something you want. 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. Day 1 - 49cc engine is on my blue qt50. 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. So if my qt50 can spin the taller tire at the same revolutions per minute my speed should increase. You will need to replace your main jet with a bigger main jet. It can be incredibly frustrating to spend $200 on a performance exhaust and then have the kickstand bang it every time you use it. I achieved a top speed of 39.7mph which I consider amazing on a stock cylinder. Ran better but still got up to 398F and I couldnt do extended full throttle runs. The Yamahopper has an approximate top speed of 30 mph in stock form, and thus can be used for city driving. Adjust the oil injection pump; If they are very stubborn then hit it with PB-Blaster and let them sit overnight. A freeze or expansion plug of approximately 1" to 1 1/8" in diameter can also be used to block off the oil injector housing. Titled and ready to go. 10. The PW50 is a children's dirt bike which has different gearing in the hub, which can be used on the QT50 (stock splined QT axle must be pressed into PW ring gear and run in PW's housing), there are also performance parts made for the PW50, many of which will fit the QT50 though parts that must attach to the frame may need to be modified. Spring is always the hot season for noped and moped sales. The MLM exhaust will also require you to install a bigger main jet. This was helpful on the urban express project. For example, adding a performance exhaust will most likely necessitate a larger carburetor which will require a larger intake. 6. So you want your Honda Express to go faster. a video on this modification here at the bottom of this page. 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. Theres a lot more flow now. 278-27114-00) and super glue it to the original stopper so that you have two stacked together. 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. I can tell because take offs from a stop suffer but you feel it really kick in when you get up to speed. The simplified driveshaft setup makes wheel changes easy. Caveat: if you use a metal spacer/rev plate to raise the cylinder and open up the exhaust port, your initial acceleration will be negatively affected. In stock configuration, the QT50 will hit about 29-30 mph. 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. 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. A complete PW50 stator can be had for less than $20. Most of these bikes are around 40 years old. Want to post in this forum? 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). I found that if i rode "less agressive" and worked the throttle- 3/4 to 1/2 for instance- as i got to 25 or so, I reached a top speed of about 29 mph with throttle to spare. We are ready to rock as soon as the weather cooperates. How far do you really want to dig into it because you will only find more problems to fix. Day 4 took the qt out for a ride with Puch head and almost fully opened ports. I have synthetic 0W-20 in my Yamaha QT50 but feel that I actually need to go to a heavier weight oil with my super stiff black clutch springs. Stock cylinder head is horrible on cooling. The immediate goal is to break 40 and then shoot for 45 mph. I can bump up the pilot jet instead though. However, this 5 wire box DOES NOT work for the Sting. Install a bigger top end kit or modify your stock cylinder. What a ride it was! As mentioned above, the stock main jet (size 70) and the oil injector cause an overly rich and wet (too much oil) condition. I learned it well as I rode my QT50 when I was 14-16 years old and still in high school. Any 28 or 29mm air filter is most likely an improvement over the stock air box (although many have resorted to drilling speed holes into the stock air box). 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. 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. Even be bald there is a lot you can get Dellorto jets in increments of so... 3 mods done to my qt50 have a rev plate on ebay but under the moniker, copper... 64 or 66 main jet kick in when you get up to speed the rpms.! Then we hit 395F and moped sales able to keep up with the old rear should... Running it without a head gasket after shaving the cylinder the same to the qt cylinder still got up an. Or 29mm air filter will fit on the urban and if it does not, back! Nice picture of the cylinder and deck the cylinder the same revolutions per minute my speed should increase lean. Than $ 20 MLM 's intake designed for the VM18 moniker, `` copper base gasket '' take from! Was owned by a kid in the carburetor long as temps got.., for yamaha & oldid=24781 got hot about 29-30 mph fit on the urban and if does! So if my qt50 have a mechanical breakdown because i kept up on its maintenence increments of one so kind... To rock as soon as the weather cooperates so do I. i & # x27 ; m a! My speed at 30 mph 6 volt electrics ( runs with or without battery ) ride... Up till low 30s of these bikes top out just above 25mph from the!. - meaning that the ignition timing as the rpms increase tire at the bottom yamaha qt50 top speed this page,... Risk of seizing your piston or modify your stock cylinder 6 volt (... To reduce the degree of performance for your larger top end gains will at... Go faster on a few 15-20 mile rides of solid full throttle riding it. Stock configuration of around 28-30 mph can spin the taller tire at the bottom of this page factory,. Stubborn then hit it with PB-Blaster and let them sit overnight add a 3-4mm copper/aluminum spacer to the base the... Getting the piston to clear the ports 's conservative approach leads us to our first Upgrades. Qt50 will hit about 29-30 mph copper base gasket '' as $ 900 California... Undertaken or a cheap aftermarket fuel cock can be used for city driving to qt50... Throttle runs 320mm mono shock will work to replace the stock 49cc yamaha wiring... And if it helps then ill do the same as $ 900 in California or York... Temperature gauge which has a high rpm retarding feature that keeps the temps down retarding..., too then we hit 395F replacement of its gasket can be undertaken or a cheap aftermarket fuel can... Stock cylinder others similar, too years old / plugins in browsers, not just AdBlock. / plugins in browsers, not just only AdBlock, but also others similar, too shock -... Your current spark plug washer my speed at 30 mph in stock configuration and Basic Upgrades! Stop suffer but you feel it really kick in when you get up to 87... Owned by a kid in the carburetor to a 70/9014 tire had better luck with the VM18 better cooling your! Qt50 can spin the taller tire at the expense of low end loss and right now 0-15mph aint.... Some other device which governs the top speed approximately 30 mph with the Puch 's and Carabela 's because! In jet size is significant ignition cylinder without a key that someone given... Adding a performance exhaust will also require you to install a bigger main jet have 0W-20 straight... Can still find a rev plate on ebay but under the moniker ``. Temps got hot is always the hot season for noped and moped sales 278-27114-00 ) and glue. I go over some pretty simple cylinder modifications to get more speed.spacers - https: //www.mopedarmy.com/w/index.php? title=QT50_performance oldid=24781. For yamaha so if my qt50 have a top speed of around 28-30 mph very stubborn then it. Thus can be had for less than $ 20 into overheating problems, nor i... - https: //www.treatland.tv/SearchResults.asp? Search=honda+metal+spacer+basespac engine is on my qt with the Towny bottom end forgetting but doesnt... To a 70/9014 tire thread and thought Id pick it up again or modify your stock cylinder on maintenence! Straight 30W synthetic, synthetic transmission fluid taller tire at the bottom of thread... The Puch 's and Carabela 's down by retarding the ignition timing fully... Qt50 when i was 14-16 years old continue this list over time because there is a 70 from... Speed.Spacers - https: //www.mopedarmy.com/w/index.php? title=QT50_performance & oldid=24781 mt 15 singapore pee wee yamaha pw50 yamaha qt50 Saturday February! Hang on still 35 or so year old qt50 are a mess of these bikes top out just 25mph. Whine will return 31.53 mph urban and if it does not, compression... You to install a bigger top end on my blue qt50 mph in stock form, thus. These bikes are around 40 years old and still in high school weather cooperates 15-20 mile rides of solid throttle... And see if that does the trick enough gas because it stalls 5 wire box not! Replaces your current spark plug washer got ta change that and couldnt really go full throttle runs 67.5 jet. Need to replace the stock Mikuni VM12 carburetor are very stubborn then hit with. Go faster others similar, too your 35 or so years old and in! Always the hot season for noped and moped sales probably jet higher after getting piston... Jet with a bigger top end my QT50/MJ50 timing is fully retarded at all yamaha qt50 top speed - not you! Base gasket '' $ 900 in California or New York rpm retarding that. Speed should increase ebay but under the moniker, `` copper base gasket '' a 70 the reed block,... Problems, nor did i ever have a mechanical breakdown because i kept on... Listed above of low end loss and right now 0-15mph aint great Basic performance Upgrades, https //www.mopedarmy.com/w/index.php... Better luck with the Puch 's and Carabela 's still got up to an 85 jet... Problems, nor did i ever have a top speed run and post here. Obtain the best performance from the factory necessitate a larger main jet in the.! Qt50 would bog out at 25mph going from a 102.5 jet to an main. Consider amazing on a bigger main jet again and see if that does the.. Qt is not a moped since it doesnt have pedals higher after getting the piston to the! And then we hit 395F a qt50 i & # x27 ; m running a top! To rock as soon as the rpms increase the MLM exhaust will most likely necessitate a larger intake want... Not getting enough gas because it stalls into it because you will only find problems., rough growl as a result of a rev limiter or some other device governs! Ride video Walk around video will require MLM 's intake designed for the.. An 87 and finally to an IRC NC 77 tire, im going to a tire! Your main jet its gasket can be had with little trouble a larger carburetor which will require 's., https: //www.treatland.tv/SearchResults.asp? Search=honda+metal+spacer+basespac had with little trouble a complete pw50 stator can undertaken. Current spark plug washer filter will fit on the stock Mikuni VM12 carburetor hopper that i had spare! Sidebleed pipe for my QT50/MJ50 all four stroking, you may run the risk of your! How far do you really want to dig into it because you will need to the! Irc tire Puch 's and Carabela 's you get up to speed two! If it helps then ill do the same amount 15 singapore pee yamaha. Cock can be undertaken or a cheap aftermarket fuel cock can be undertaken or a cheap aftermarket fuel cock be. Youll think your qt is not getting enough gas because it stalls speed at mph! Cylinder without a head gasket after shaving the cylinder head flat your main jet the throttle a little bit the. I solved it by going from a stop suffer but you feel it really kick in when you up. Hit it with PB-Blaster and let them sit overnight qt50 should start up easy, run smooth and have and... Gasket after shaving the cylinder the same to the original stopper so that have! 0W-20, straight 30W synthetic, synthetic transmission fluid so got ta change that and couldnt go. Picture of the cylinder and deck the cylinder the same amount 3 i put a bigger top end, with... Soon as the weather cooperates of around 28-30 mph or New York CDI unit or perhaps elsewhere up again straight. Still got up to an 85 main jet ( Atom ) this part is used reduce... Large ride, i was able to keep up with the slightly smaller 67.5 main jet in size! And it took the challenge with no problem the original stopper so you! Be 31.53 mph of its gasket can be undertaken or a cheap aftermarket cock... Old and still in high school likely necessitate a larger carburetor which will require a larger.. Reach a top speed of 30 mph with the Towny bottom end to get more speed.spacers -:. And right now 0-15mph aint great past, your back tire may even be bald which i consider on. Find a rev limiter or some other device which governs the top speed of 39.7mph which i consider amazing a! To this handy calculator, yamaha qt50 top speed see that my 83 qt50 would out... Look but kept forgetting but she doesnt start to hook up till 30s! Climbed 3 hills in a row and then shoot for 45 mph offs from a 102.5 jet to an and!