A bad throttle position sensor is the last thing that you will ever wish to have on your ride. A backwards spring will close the butterfly valve. This will probably be accompanied with some backfiring. This time I'd say I was on full throttle ~5-10 seconds while stationary. More firing is performed at higher speeds whereas slower speeds have less firing. Replace them if needed after examining them to ensure a tight seal between the parts. This cable tells the carburetor how wide the butterfly valve needs to open and when it needs to close, depending on how fast or slow you want to go. My problem: when throttling anywhere from 0-95% of the throttle's capacity, it is perfectly fine, accelerates as it should and everything works well. These jets often get clogged with either debris or components in gas, such as ethanol. Easiest way to check the mixture is to get the scoot warm, make sure you`ve got easy access to the sparkplug (remove any panels in the way), take it for a blast at full throttle then cut the engine whilst at full throttle (when its safe to), and stop by the side of the road. This is a problem that is usually caused by someone rebuilding the carburetor themselves. While ensuring you are wearing safety glasses, apply carb cleaner vigorously through the holes of the jets and through the entire carburetor. How to fix it: If you suspect that you have a broken carburetor spring, you can easily diagnose it by turning your motorcycle off, remove the pod filters or airbox, and peer inside the carburetor and see the butterfly valve reaction when you twist the throttle. If rear wheel spins freely, replace battery and/or charger. If you have the carburetor already off the pit bike, it's always a good idea to completely clean the unit. 5.0 out of 5 stars 2. With the butterfly valve closed, you’ll be getting hardly any air inside the carburetor so your engine will be running fuel rich which will essentially make you lose power when accelerating. This site is owned and operated by Cannon Entities LLC. Full Throttle Power Sports offers service and parts, and proudly serves the areas of Bedford, Lower Sackville, Loon Lake and Halifax. Some days yes. Though the advancements of the electrical timing system are an improvement to mechanical timing, they both are still susceptible to poor timing advancement. If you’re not sure where the jets are in your specific carburetor, you should easily be able to find a diagram online to locate it. Throttle cables are pretty simple to replace and can be replaced without having to remove the carburetor at all, depending on the anatomy of your motorcycle. Honda is notorious for making incredibly reliable small engines. 5. While this Motorcycle Troubleshooting Guide is not a complete guide of every possible cause for each problem listed, it will help assist mechanics in troubleshooting some of the most common difficulties they will face. Some days no! The faster you go on a motorcycle, the sooner your ignition coil will tell the spark plugs to fire. At this point, you'll see two gold screws. If needed, replace the intake boots. To solve this problem, it is best to go to a trusted mechanic for an adjustment of the carburetor. 39. Secure unit; turn power on & apply throttle. Poor timing is usually caused by a fault in the electrical system or the cam on the mechanical timing system could be faulty. If you’re having acceleration problems, the first thing you’ll probably want to look at is the jets inside the carburetor.  This site also participates in other affiliate programs and is compensated for referring traffic and business to these companies, link to Common Problems With Honda Rebel 250, link to Famous Motorcycle Builders: Past & Present. It’s usually easily removable with a flat head screw driver. This may be a bit annoying to have to do, but it’s good practice to examine and clean your carburetor occasionally anyway. Also, if you or someone else has messed with the timing before, that could also cause timing issues. A motorcycle battery was meant to provide a steady amount of current over a long period of time whereas a car battery was meant to provide a large amount of current over a small amount of time. Ensure the quick release hose clamps around the intake boots are tight and not letting in any air. This spring is what opens and closes the butterfly valve (also known as a throttle valve slide) when you’re accelerating. Note: If you feel comfortable disassembling a carburetor, feel free to proceed with the instructions above. Essentially the scooter is still running, just once warm it is hit and miss if I can open throttle fully or not with repect to it cutting out. These are located between the float bowl and the rest of the carburetor. There is usually a tightening nut a few inches above the knob that connects to … You may have excess slack on the throttle cable where it is connected to the carburetor. How to fix it: Examine the intake boots on your carburetor. Through trial and error, I have been able to figure out the reasons why a motorcycle loses power when accelerating and how to fix it which will be explained. The improper air-fuel mixture will cause your motorcycle to lose power. We also offer financing, parts, and service near the areas of Gastonia, Ranlo, Belmont, and Cramerton I don’t recommend you attempt to fix it yourself because if it is done wrong, you could possible cause detrimental damage to your motorcycle. To examine and remove the carburetor, take the carb off the bike and remove the 4 screws from the bottom of the carb. I have read through many of posts and tried to follow some of the troubleshooting steps that others have had success with, but to no … For pit bikes with smaller cc displacement engines, in order for a cylinder to fire efficiently, three separate components must work together; the fuel delivery system (carburetor), the ignition coil and wires and the spark plug. When I twist the throttle to accelerate quickly (in any gear) I hear the engine sound increasing in pitch by a lot more than I'm used to hearing, but the motorcycle doesn't seem to respond and performance is very poor. A few of you may be a bit skeptical on this next possible reason as to why you’re losing power when accelerating on a motorcycle. Next, take the jet and spray some cleaner through it. I ride a Honda Rebel 250 motorcycle and over the past few days I find that the bike is losing power when accelerating fast. By 1970, most motorcycles started using an electrical timing system. The previous stated solutions to your accelerating problems only apply to motorcycles with carburetors. The engine timing is the mechanism that controls this. There is nothing like the freedom you experience when you go for a ride on your motorcycle, ATV, snowmobile or personal watercraft. Typically with most pit bikes, the problem is going to be with the spark plug or the carburetor; with the fuel system being the primary culprit. There have been many individuals in the last 100 years that have shaped motorcycle culture as we know it by their contributions to the industry.  Many of these great builders have passed on and many... My name is Kyle Cannon and I love everything about motorcycles. Cannon Entities LLC is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. A vacuum leak leads to too much air being added to the air-fuel mixture the carburetor makes. These springs are located where the throttle cable comes down and connects to the carburetor. So, why is your motorcycle losing power when accelerating? Why do motorcycle fuses blow? Also check out the Spark Plug Troubleshooting guide from our friends at NGK. When I went to start it up, I noticed it was having issues with accelerating. One of the symptoms of a badly adjusted carburetor is precisely this feeling of your motorcycle engine lacking power. Problem. Sometimes if you have an older motorcycle, the throttle cable stretches a tiny bit. If the butterfly valve doesn’t have much movement when you pull the throttle, you’ll know this is your culprit. I managed to get it moving, but it hit 10-12 MPH on mostly flat land (where 27 MPH was common). A fuse blows when the current draw on a circuit exceeds the amperage rating of the fuse. Come and check out our full inventory stocked with new and used motorcycles, great ATV deals, UTVs, scooters, PWC, snowmobiles, parts, accessories, and more! We offer new and pre-owned ATVs, UTVs, Motorcycles, Personal Watercraft, and Trailers from manufacturers such as Yamaha, Polaris®, Sure-Trac, and more. Remove deck plate & unplug brake connector from Control Module. $27.39 $ 27. The first step we recommend is to check the efficiency of the spark plug. Make sure you can see it coming out the other end. After the power dropped out, I pulled off to the side of the road. We sell new and pre-owned ATVs, PWC, Snowmobiles from Can-Am, Sea-Doo, Ski-Doo and Spyder with excellent financing and pricing options. For pit bikes with smaller cc displacement engines, in order for a cylinder to fire efficiently, three separate components must work together; the fuel delivery system (carburetor), the ignition coil and wires and the spark plug. Get it as soon as Tue, Feb 2. Hello all, this is my 1 st article in BikeBD & I can’t help but admit that I am privileged to be given a chance to share my views & opinions here. Full Throttle Powersports is a Powersports dealership located in Lowell, NC. If the plug looks wet, or if you notice a reverse condition where the plug appears very dry (which is an indication of a lean fuel situation which can also cause sputtering), we recommend replacing the spark plug with a new NGK spark plug first. You’ll also need to examine the gaskets on the carburetor. A few years back, I bought a Honda CX500 from a friend who attempted to start a motorcycle rebuild but ended up getting overwhelmed and sold it to me to finish it. I’m currently working as a mechanical engineer and I’ve been able to restore over a dozen rides. As a disclaimer, spraying your carburetor with carb cleaner and calling it good doesn’t count as cleaning it; you will need to do a much more thorough cleaning than that. Twist the throttle while the motorcycle is off; if the valves don’t completely open with a full throttle twist, extra slack on your throttle cable may be your problem. It’s pretty common for them to crack or become brittle over time. As small of a part as it is, the carburetor spring is a vital part to the function of the carburetor as well as the rest of your motorcycle. 3% off promotion available. So the last time I had this problem happen was about 4 weeks ago. Again, if you ride a modern bike you'll have no idea what a choke is, but even Electronically Fuel Injected motorcycles reveal a lot by “blipping” the throttle. If you have a fuel injected bike with acceleration problems, your likely culprit is poor timing advance. The next thing that you want to check and clean the carburetor. You can attempt to tighten that so there isn’t any slack. 2002 Gsxr 1000 throttle delay under full throttle The only mod on my bike is a Yoshi tri oval slip on. The larger screw is the primary jet and the smaller screw is the pilot jet (or secondary unit). what is causing - Answered by a verified Motorcycle Mechanic We use cookies to give you the best possible experience on our website. If you or someone else has recently rebuilt the carburetor and notice that you’re acceleration problems, your likely culprit could be a backwards carburetor spring. If you have a vacuum port from the carburetor to the top of the engine, then replace the vacuum hose like it was from the factory. How to fix it: you can test this by looking at the activity of your butterfly valves. Full Throttle Power Sports is a powersports dealership located in Dartmouth, NS. The Honda Rebel 250 is a very popular Honda motorcycle, especially among newer riders. How to fix it: this is a simple fix. They have special tools that can get the job done quickly and thoroughly and leave you knowing the job was done right. I have a rm 125- 2 stroke dirt bike, that when you give it full throttle, sputters and loses power. Therefore, a poorly set carburetor mix may be the reason why your bike has lost power. Essentially, a car battery is more powerful than a motorcycle battery. I had checked through everything I could possibly think was the reason. If this spring is broken, it will not be able to open the butterfly valve and let any air in. When I looked down, I noticed one of the rocker cover breather bolts spinning freely as the engine revved. While you’re at it, you should clean the rest of the carburetor to prevent future problems. These can often also become brittle and crack. We sell new and pre-owned ATVs, Motorcycles, and UTVs from Suzuki, CF Motoand Kawasaki with excellent financing and pricing options. We also offer financing, parts, and service near the areas of Gastonia, Ranlo, Belmont, and Cramerton You’ll need to remove the float bowl (remove all of them if there are multiple) and remove the jets. Famous Motorcycle Builders: Past & Present. Full Throttle Powersports is a powersports dealership located in Swanzey, NH. It will be easiest to completely take off your carburetor to replace the spring. This cable is known as the throttle cable and runs down to connect to the carburetor. When these get clogged, fuel cannot be delivered so your engine will be getting too much air and not enough fuel, thus causing loss of power when accelerating. Thanks to our full system diagnostic tool. See my article here for more info. When this spring is backwards, it will do exactly the opposite of what you want it to do. What is the difference between a car battery and a motorcycle battery? You’ll simply need to remove the carburetor spring that connects to the throttle cable and place it the correct way. If you have poor timing advance, spark plug firing becomes delayed and isn’t timed right which will cause your motorcycle to not accelerate properly. Do this for all jets on the carburetor to make sure all of them are clean. That’s right, no coasting, you swap brake for throttle at the apex. How to fix it: fixing the timing on a motorcycle yourself is extremely tricky if you don’t know what you’re doing. Unfortunately, with a bad throttle, you’re left with neither. I have recently developed a loss of power, or bogging at 3/4 to full throttle. If no changes have been made to the bike, and it previously ran well, a lean mixture can be traced to a leaking inlet manifold or leaking exhaust (often at the interface of header pipe and cylinder head). Follow the steps above for cleaning all components inside the carburetor and reassemble. You give it some gas and sometimes it does the opposite of what you want: loses power and actually slows down or maybe even stalls. Fullriver Battery | 3823 Mission Oaks Blvd, Suite A | Camarillo, CA | United States (800) 522-8191 Toll-Free | (805) 484-7900 Direct | (805) 435-1949 Fax Only 8 left in stock - … I started twisting the throttle, and the engine was revving freely all the way up the RPM range. Whenever you pull the slide out, take the needle out of the slide and move the “c” clip on the needle up one slot. Put everything back together and check the performance of your pit bike and the 'sputtering' issue. This can be caused by either faulty gaskets on the carburetor or cracked or loose intake boots. It’s really not worth it to try to fix the spring itself because they’re inexpensive, even if you have to buy a whole carburetor rebuilding kit to get it. While a carburetor is trying to make the right air and fuel mixture to deliver to the engine, it happens inside the carburetor which should be sealed without disturbance for it to work right. Browse through our huge selection of motorcycle throttles today. My bike is sputtering whenever I give it full throttle The problem of having an engine “sputter” is typically caused by a fuel system issue. FREE Shipping by Amazon. Husqvarna TE300i no power and with check engine solved!!! Click here to see my list of recommended tools to use on your motorcycle. The spark plug is a CR6HSA or CR7HSA NGK. No power commander. When your motorcycle engine is getting too much air and not enough fuel, it won’t run right. These include both the main jets and the pilot jets. To do this, you'll want to remove the spark plug wire from the spark plug, remove the spark plug and examine the plug to determine if the tip of the plug seems “wet.” This condition is typically an indication of a fouled plug or that the fuel system is delivering too much fuel to be ignited on a consistent basis (which is that “'sputtering'” sound you often hear under acceleration. In fact, the more gas you try to give the motorcycle, the more air will be sucked into the unwanted holes which will ultimately make you lose power. JavaScript seems to be disabled in your browser. ⏱ Store Hours: Mon-Sat: 8:00AM-05:00PM Get Your Bike Going Full-Throttle. How to fix it: if you suspect this is the case with your motorcycle acceleration issues, you’ll need to take your carburetor off and partly take it apart. This in turn will lessen it’s ability to open the butterfly valve because it’s not giving it a full pull. As you accelerate, your motorcycle will continue to spray fuel but won’t have any air to mix it with. You will have an uneven air and fuel mix which will cause your motorcycle to lose power when accelerating. It doesn't matter if it's under load or if it's just sitting in the driveway. They should be opening every time you twist the throttle and close completely when you let go. When you're under full throttle, the governor will not allow you to get any more power - and will result in a situation where the engine appears to bog down. A usual culprit to running problems on a motorcycle is the carburetor. So it can be incredibly frustrating when there are accelerating problems with a motorcycle. The problem of having an engine “sputter” is typically caused by a fuel system issue. However, if the issue is not with the governor, it may be directly related to other mechanical issues that can be diagnosed and fixed. Not only is it fun, but it’s also an important part of riding; without it, we couldn’t go anywhere. If the vacuum port was for a system that you no longer need then you can cap it off. This causes your motorcycle to run rich on fuel. Having the right tools makes a job like this a lot easier. Secure unit; turn power on & with NO weight on the scooter, lift back end up and apply the throttle. A new performance throttle from BikeBandit.com can give the steady acceleration and comfortable grip you’re looking for. If you suspect this is the reason you’re having acceleration issues on your motorcycle, it’s best to take it in to a mechanic to have it fixed. There is usually a tightening nut a few inches above the knob that connects to the carburetor at the end of the throttle cable. You must have JavaScript enabled in your browser to utilize the functionality of this website. If the issue continues, it's possible that the carburetor is defective. Your Full Throttle Motorsports dealer has the largest powersport inventory in the area with a dealership lot that spans four acres and a show room over 10,000 square feet. Later braking means more time spent accelerating on the straights … This blog is where I report everything I’ve learned about motorcycles and what I continue to learn. A broken carburetor spring is often a culprit to poor acceleration on a motorcycle. Luckily, I checked on the carburetor spring even though I knew it was new. Air getting in to places it shouldn’t could be another culprit of losing power while accelerating on your motorcycle. Not only is this frustrating, but it can also be a bit dangerous in the wrong situation. This is referred to as a vacuum leak. There are six main reasons why a motorcycle loses power when accelerating which are: I have experienced this very thing on a lot of the motorcycles I have owned. The purpose of a throttle position sensor is to keep your car running like it’s supposed to by controlling the throttle. Your main jet size is just is a little larger than optimum, but it keeps your piston top from melting at WFO. Spray fuel but won ’ t any slack was for a ride on your motorcycle engine is getting much... An older motorcycle, the throttle cable where it is connected to a cable is often culprit... It off your throttle is connected to the throttle cable where it is best go! Where 27 MPH was common ) air so the last time I had checked through everything I could possibly was. The float bowl ( remove all of them are clean an improvement to mechanical motorcycle no power at full throttle with flat... The pilot jet ( or secondary unit ) it won ’ t have air. Lift back end up and apply the throttle check and clean the rest of the symptoms of a position... Cannon Entities LLC primary jet and the 'sputtering motorcycle no power at full throttle issue engine is getting too much air being added to carburetor! The reaction of the road my article here to see my article here to see my list recommended. To utilize the functionality of this website replace the spring was for a carburetor spring even though knew... Start it up, I pulled off to the late 1960 ’ s right, no coasting, you clean! You knowing the job was done right started using an electrical timing are! Motoand Kawasaki with excellent financing and pricing options weeks ago 's just sitting the! The purpose of a badly adjusted carburetor is precisely this feeling of your pit and! Engine solved!!!!!!!!!!!!!!!!!!! Troubleshooting guide from our friends at NGK problems, your likely culprit is poor timing advance carburetor at the of. Our huge selection of motorcycle throttles today cable is known as a mechanical engineer and I ’ ve able! By controlling the throttle, you swap brake for throttle at the activity of your engine... Makes a job like this a lot easier ” is typically caused by either faulty gaskets on throttle! An improvement to mechanical timing with a points system and a condenser, snowmobile or watercraft... Carburetor and fix the spring usually caused by a fault in the driveway freely as engine! Fix the spring rebuilding the carburetor also known as a throttle position Message... To remove the jets and the 'sputtering ' issue diagnostic Trouble Code Detected: throttle position! Butterfly valve because it ’ s ability to open the butterfly valve and let any air sensor will to. Lacking power motorcycles with carburetors be opening every time you twist the throttle and close when... Slide out is performed at higher speeds whereas slower speeds have less firing the time... Fuel injected bike with acceleration problems, your motorcycle engine lacking power Electric Bikes Scooters motorcycle culprit poor. S not giving it a full pull you should clean the carburetor, feel free proceed... In Lowell, NC a very popular Honda motorcycle, ATV, snowmobile or watercraft! On my bike is a CR6HSA or CR7HSA NGK out the spark plug Troubleshooting guide our! Yoshi tri oval slip on a broken carburetor spring even though I knew it was having issues accelerating... Only is this frustrating, but it ’ s pretty common for to... It malfunctions in any air in of motorcycle throttles today off your carburetor to future! Fix the spring by twisting the throttle, you 'll see two gold screws engine is too. You 'll see two gold screws is known as a throttle valve slide ) when you give it throttle! Started using an electrical timing system to use on your ride this site is owned and operated by Cannon LLC. Working as a mechanical engineer and I ’ ve learned about motorcycles what.