Neal Hendes – Page 14 – Project Dirt Bike

Starting an XR when you don’t know what you are doing can be a hard task, and that is speaking from experience. Let me tell you a quick story to illustrate my point… Before I bought my XR I had never owned a dirt bike, although I had ridden a few that had belonged to friends when I was younger. So after deciding to scratch the itch and buy my first, I browsed gumtree and was delighted to find an XR250 in the next town. This is the same one I have as a dirt bike project on this blog. I turned up late afternoon, being dropped off by car from my wife, and had a quick look round the bike. You know how it is, you see it and know you are having it no matter what, and pretty much over look everything as excitement takes control and blinds you to any potential problems. We exchanged cash for log book before the seller returned to the safety of his house. His part of the exchange was complete and I was left on the drive ready to start her up and take her home to meet the family. Straddling the bike I attempted a couple of kicks with no joy. That’s weird, this guy has just started it no problem and now it won't start! I can’t recall how many kicks later ( I know my leg was aching) when I noticed the curtains twitching and eventually the seller comes back out. “Have you had one of these before...do you know how to start it?” “Yes of course…. I’m not sure what’s wrong with it” I replied. “Guess you better give it a try”. With that the bloke jumps on, explains what he is doing and starts it no problems. Embarrassing was an understatement as I'm positive he knew I didn’t have a clue. I couldn’t wait to get out of there… So How Do You Get An XR 250 Started? Like all things it’s easy when you know how. I shall talk you through the starting procedure for my 1991 Honda xr250 and i’ll include pics about the different parts to make things as easy as possible to understand. So, my Honda XR is a kick start and does not have any electric start so to get the bike running you will be using the kickstart, choke, decompression lever and the throttle. After you have gotten to know your bike you’ll become familiar with starting it and learn if it requires more or less choke, more throttle etc. Below i’ll explain the steps for starting, and then below that I'll talk about what each function the different parts does, so you can better understand what is going on. It’s important to add that I'm no mechanic, it’s just what I have learnt during my time as a biker and since owning my XR. More detailed and knowledgeable descriptions i’m sure can be found on the web. Assuming the bike is being started from cold... Step 1 - Turn on the fuel Simple as that.. But surprising how often I forget. Here is a pic of my fuel tap in various positions. In the picture the fuel tap is currently set to off. So what ever the little handle is pointing at is the current position. Step 2 - Full Choke My bike likes full choke when starting cold so this little lever is pushed fully up. I can set the choke to half open by positioning the lever near horizontal ( one position down from fully up). To have no choke at all the lever will be fully down. Fully Down = choke shut off, Half Way = half choke, Fully Up = choke fully open I generally get started on the first or second kick, at which point I turn the choke down to half, then as the bike warms you can hear it needs to be closed off. If starting the bike after it’s already warm , for example you have taken a break during a ride and turned off, then no choke would likely be required. Step 3 - Cycling through the kick start Next up I place my foot on the kick start and push it through the cycle without giving it a kick. This may mean pushing it down a couple of times. What I am aiming to do here is by feeling the level of resistance you can work out when the piston is at the very top of its stroke cycle, so when I decide to kick it over you get a full rotation and better chance of the bike starting. You may at this point need to make use of the decompression lever. Step 4 - The Decompression Lever During the previous step you would of attempted to get the piston to the start of the stroke by feeling the pressure on the kickstarter. When you do this the piston is on the compression stroke and it can become quite solid under foot, by squeezing the decompression lever it will release a little bit of pressure to help you get over this. Then the kickstarter will feel different as you push down. (but don't push down yet) It is when you have just inched past the 'solid' part that you will have the enigine ready to give it a hard kick. Step 5 - Kicking The Hell Out Of It Ok so not literally, but when you are ready you will need to put a good firm hard kick in to get the engine started. If you are unsuccessful then simply go back to the first step and try again. Side Note - The Throttle When you are set on everything in the previous steps then you will naturally have your hand on the throttle most likely, whilst sitting on the bike ready for the 'big kick'. I dont know about everyone else but for my bike I do not require the throttle to start her but will give it a couple of blips after it has started and as it warms up. Just be careful you dont flood the bike prior to starting. 6 Reasons Your XR May Not Start At some point you will have a time when your bike will not start for anything. Man it is frustrating! Although it could be for a whole manor of reasons I thought I would list down some of the common reasons and fixes that go along with them so you have something to refer to if you are in this situation. In no particluar order.... Gone Off Fuel Arguably the most common reason your XR wont start is stale fuel, and one I have become familiar with over the years of riding. If you bike has been sitting , even for a short while, then it is the fuel in the carb that will likely of gone off . It's an easy fix: simply by tilting the bike over as if you are going to lay it down, fuel will start to run out of the overflow pipe. This means the fuel in the carb is running through and new fuel is replenishing it. Obviously if your bike has been sat for an age then the fuel in the tank may of also gone stale. You can smell stale fuel. It has a varnish like odour to it. Turn The Gas On I know this sounds like a silly one. Especially as it is in the starting procedure steps above. Maybe it's just me but it's worth a double check...enough said! Spark Plug Needs Replacing The spark plug is there to ignite the fuel mixture so if your spark plug isn't sparking then there is a zero percent charge the bike will start. Sparks plugs will need to be replaced after a certain amount of milage. This could be 15'000 miles for example. An indication that your plug needs channing could be loss of power, or engine spluttering. Regardless of that, if it's dead it wont spark in the first place which means your bike wont start. So How Do You Test A Spark Plug? Take the plug out and start by having a look at it. If the plug is heavily soiled and black then if it's not totally done for, then it is likely to be near done. There is a couple of things you can do to see if its any good though. The first can only really be done with a second person because it's a bit of a stretch, but basically return the plug to the cap after you have unscrewed the plug from its socket in the cylinder head. Then ground the plug on section of the frame. Now when you go to kick the bike over you should see a spark between the electrodes. You can see how having a second person is required, because you are not likely to be able to hold the plug against the frame whilst kicking the bike over. The more technical way of testing a spark plug is with a multi meter. Using one of these we can check the resistance of the spark plug . So first set your multimeter to the Ohms setting and select a range of around 20k. This is because we are expecting a reading of between 4 and 8 thousand ohms. Place one prong of the multimeter on the end electrode with the white porcelian and the other on the small electrode at the opposite end. The multimeter should then read somewhere between 4k and 8k. Next you want to do a continuity test so set the multimeter to the continuity setting. Start by placing the first prong on the thread of the spark plug and the second prong on the very end piece of metal (the piece that curves over), which is the ground electrode, and your meter should have a constant beep in most cases and give a reading of .001. Finally we can also check to make sure the plug is shorting out. Do this by putting the meter selecting to the max number of ohms. Place one prong on the electrode atthe very end , the same end as the white procelian, and the second prong on the ground electrode. You should have no reading if the plug is good. One thing to be aware of is that your plug maybe reading as though it is failed the above tests but this couold be due to carbon build up. You can in this case use a small wire brush to brush away the black carbon and test again. If your plug is heavy in carbon then the engine is running to rich. Related: I have a dirt bike maintenance hub on the website to help with all this sort of thing if you get stuck Haven’t got the start cycle correct Particularly if the bike is new to you then you may just not be giving it the best chance of starting because you havent got the start cycle down. That was my case anyway, like I mentioned in the start of this post. Air filter Dirty? Your dirt bike air filter would have to be extremely dirty for it to prevent the bike starting at all. The filters job is to allow clean air in to then be mixed with the fuel before it ignites. If this was cut off you would have issues. A clogged filter would cause the bike to run rich and this would produce arbon build up, including on the spark plug as mentioned above. You would likely find problems such as this before the bike ends up not starting as solely due to the air filter. In any case it is a good idea to check your air filter as part of regular maintenance which would avoid these issues. You May Of Flooded Your Bike Bikes can become flooded after you have try to start you bike a few times without being able to get it going. Especially when the choke is fully open. Flooded means to much fuel/gas has reached the combustion chamber so you will need to reverse this to get it going. Turn the choke off, turn off the fuel at the tap, open the throttle fully and kick it over few times. This should clear it. I then turn the fuel on and try kicking it over before giving it choke, then introduce the choke if needed. Hopefully you found this post helpful, it would be great to hear your comments in the box below and let me know if you have any questions. Until next time....