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Found 35 results

  1. frontline510

    Need help with Timing

    Hello everyone, I am currently rebuilding my top end on my 2001 Wr250f. Everything has been going smoothly until it came time to set the cam timing. I have set the motor to tdc, and slipped both cams under the timing chain. No matter what I do, I cannot seem to align the camshaft timing marks level with the head of the motor. The exhaust side cam aligns perfectly with the dot sitting flush with the head line. The intake side cam mark always ends below the head line or above. Neither way looks natural. The dot is either too deep to the point I can't see it, or too high to the point it floats above the head line. Which way is correct? Thanks in advance for any input.
  2. Hi all. I have a 1975 suzuki RV125 that has a magneto, points/condenser and is a 6V system. I need to pull the flywheel and points plate off do replace the crank seal and I am thinking I should just replace the points and condenser since, well, I suspect that are original yet! I have the workshop manual and have attached the relevant pages with respect to setting the timing. I *THINK* I understand how it all works (Have very little experience with points), but I'd like confirmation before I did in. So, here's my understanding: From the manual, it appears that the point plate cannot be rotated to advance/retard the timing, only the point gap. It also appears that when the points are closed, all current flows to ground and no spark. Using a dial gauge, I'll find TDC on the piston. I'll hook a multimeter up to ground and to lead stated in the manual and (here's where I'm guessing because I don't have this "special" tool) and test for continuity. The manual has me rotate the crank backwards (clockwise) until "the sound dies away" (assuming continuity breaks, meaning open points). At this point, the dial gauge should read 2.41mm (22deg before TDC). It's my understanding that if I set the point gap appropriately to spec and have them close/open right at this point, I'll have spark at 22deg before the piston reaches TDC. Seems simple enough, but it seems odd to me - is this setup standard or is this opposite of standard. I could have sworn when setting the timing on a 73 Honda CL 350 that the ignition sparked when the points closed. Also, in this setup, the points open at 22 deg before TDC, but must close at some point after that and remain closed until it rotates around again to get to 22 deg - it just seems odd to me you'd have a wearing/maintenance type of item like points conducting current more often than not. At any rate, maybe I'm all wet and have this all wrong. Thoughts? Thanks, Andy
  3. Hey there! I'm new to Thumper talk as a member but have read many help topics over the years, time to bite the bullet and get on board! Well To start I'm not new to working on bikes, Ive always done all the basic work on my Yamaha's, 3 to be exact. YZ250F, WR450F and now a WR250F. I'm also an HVAC Tech by trade so the electrical trouble shooting experience helps. I just bought this 2002 WR250F and It only started once and ran for about 30 seconds, sounded good. After that it wouldn't start, it gave a few false burps but nothing. Popped a few times on third kick with out starting but I was guessing it was fuel I dumped in by opening the throttle. I got spark! To my knowledge, what i was told by seller and from what I've seen upon opening it up, it has a 290 big bore kit, new valves- (I checked clearenses, intake in spec .13, exhaust say's .17-.22 I have .23) Not sure if thats a determining factor?? It also has newer cams and a decompression cam. NOTE, I HAVE NO EXPERIENCE WITH 290 BIG BORE KITS, JETTING REQUIERMENTS etc... This may be the entire issue.... I took my carb off my 2002 YZ250F and put it on this bike because I know it works. I wanted to try and get it going since the carburetor that came with the bike was in a thousand pieces when i bought it. (Parts needed and on order, waiting). There is not much difference but...??? So i guess this is where the rest comes in. I went through the entire electrical system and ohm'd out everything accept the CDI box. see pictures. I couldn't find anything in the manual as far as checking ohm's. ?? I would think it would say but I didn't see anything. So here I am, is it just the carburetor? I mean it did run, it started with out the choke on like second kick and ran for 30 sec hand off throttle! I kicked my brains out two separate days checking different things and nothing after that. Please help! HAHAHA! Thanks!!
  4. Hi all, I took apart my '86 Honda XL600r because the spark plug thread was stripped. Now I am in the process of putting everything back together but I have some questions. Also this is my first time taking apart a 4-stroke. My first question: Is my timing chain worn out? I can just lift it very slightly but it looks pretty tight and cannot move it a teeth when the tensioner is on. However the hole on the tensioner is not pointing up anymore but slightly to the back. My second question: When re-installing the timing chain I put the cylinder on Top Dead Center and tried to put the timing chain on the timing sprocket as precise as possible, however the marking stripes are slightly of when installed, if I move the chain a tooth it will be again too far of. Can I leave it like this? And is this adjusted by setting the valves?
  5. Pierre Legrand

    CRF450x Throttle Response off of Idle

    Using this short video that I have cued up to make a point. Is it possible to get a CRF450x to respond off-idle like this Husky? Just want to make sure that I have a realistic goal for my CRF450x...put in a JD Jetting Kit last week and have a Boyesen Quickshot3 and RD Fuel screw...all of these items have gone a long way towards cleaning up the bike's goofy EPA jetting. Have also gotten rid of backfire screen, pink wire mod, opened up airbox,...but my bike still isn't this clean off of idle. Is this just a feature of the CRF? Or can I reasonably expect to get it running as clean as this Husky? Thank you for any help.
  6. Kraut91

    2009 yz250f HELP!

    Tore bike down to check valve clearances, bike runs great. When I check with a feelers gauge I can't fit the .10mm gauge in, the biggest I can get is the .04mm and I can't seem to get my timing marks "I" and the marks on the cam sprocket to line up correctly am I doing something wrong pls help. Timing mark on flywheel "I" set at TDC and piston is all the way up. Any help would be appreciated.
  7. Hi all, so I recently snagged an 02 WR250f off of Craigslist that "blew while riding" and was seized and wouldnt turn over for dirt cheap as a project bike to fix and flip. (story of rebuild at the bottom if interested). I bought new parts, put everything back together and am having trouble setting the timing. Ive been down almost every thread out there in search of an answer and cant find anything conclusive. SO, Ive put the engine at TDC and set the intake and exhaust cam marks at the top of the head, confirmed that there are 13 pins between top timing marks, and that the lobes are indeed pointing away from each other at the 11 and 2 positions. After all that, I can "kick" the bike over by hand, easily. it feels like there is no compression and one of the valve sets is opening too soon, or late. Ive moved both cams forward and backward one tooth each way, experimenting, hoping to find a position that will run. and cant seem to get it to work. At one point, it did start, but would only run at mid to high rpm. but I dont remember what position I had the cams. I've also read about putting a yz cam in the wr, no clue if thats been done or not (how can you tell?). so that might also be throwing me off a little. any help would be awesome! -Evan Rebuild Story: So the head looked to be brand new or rebuilt as it was shiny and new looking and the rest of the motor had a used patina. It turns out the water counter balance gear had taken a dump and taken out the water pump gear in the process and had jammed the engine from turning. So I got a new counter balance gear and water pump gear, threw it all in and noticed the counter balance on the other side of the engine from the gear (next to the timing chain) was rubbing on the timing chain guide. It was making contact, but was still able to rotate all the way around. I am guessing that is what caused the gear to shatter. So, I used a dremel to grind the back side of the guide down just a tad where there was a wear mark and there doesnt seem to be any more contact.
  8. Hey everyone, new member here. I recently traded my 2001 Honda 250EX for a 1985 XR200R. The bike is tight all around and looks like it wasn't used much in its life. However, there is a noise coming from the engine that's not from the crank. It's up in the head somewhere. I adjusted the vales and started the bike up, only to hear a slightly quieter noise which led my father and I to believe that it's the Cam chain. If the bike ends up needing one, where can I find an aftermarket chain? I've checked eBay, xrsonly, and the normal part sites and I am not able to find anyone who has a chain in stock. I called my local dealer and they said they could get one for $70, but I just think that I can find it online for cheaper. It doesn't have to be OEM. Thanks
  9. Anyone running a Vortex ignition on a YZ250F 2014-2018, or 450 for that matter? What advantages does it have over tuning FI/IG with the GYTR power tuner, and are there maps readily available for stock or mod and race fuel? I've messed around with the GYTR tuner on one of my bikes- 2017 YZ250F with bolt ons and VP racing fuel, but there is a lack of maps to run and I've heard there is more power to be had with the Vortex Ignition. I'm aware there are other less costly avenues to add horsepower.
  10. So, I picked up a '03 CRF150F a few weeks back. Found out later that it had been rebuilt but UTI, supposedly. It has a BBR exhaust and has been re-jetted with a BBR jetting kit. Ran good until it started having difficulties starting. Changed the oil and it made it easier to start for about a week. Put in a new Rev Box because that's what it had in it, and that has fixed the hard to start issue. But even more lately, there's been a knocking or clunking sound from the bottom end of the engine. You can only hear this knocking sound though when the engine is returning to idle after revving it in neutral. And it has this knock or clunk whether its cold or warmed up, although it does get louder and more frequent when it's warmed. Don't know what it is and haven't figured that out, but when I was test driving it, I got up to fifth gear and all of a sudden it sounded like a valve or something from the top end broke. It was if the engine lost all compression because you could hear the air just blowing in and out of the cylinder. Pushed the bike forward and I could feel that the engine wasn't seized up, but trying to start it with the kick start wouldn't work. Wasn't able to start the bike so I removed the engine and disassembled the top end expecting to see a broken valve or one that wasn't seating right. However, the cylinder head is black and has quite a bit of carbon buildup, so I don't know if that would cause it. Or maybe a valve is out of adjustment or the timing? The connecting rod seems to be tight enough because when you pull the piston up and push it down, there's no slack, except for side to side, which is normal I believe. Valves? Timing? Carbon buildup? Something in the lower end? Any ideas?
  11. I've been doing research over week now. Bought a 04 crf250r for $900 on terms it needed a cam chain. Come to find out the cam chain tension failed and the chain was shot. However there was a surprise. the left cam lobe closes to the cam wheel (in the head) destroyed the heads housing around the valve. Yes destroyed. Chucks of metal were found and the cap above the valve (under the cam lobe) was also destroyed and chewed up. The bike did run before i opened it decently well but did make noise (2nd 3rd kick). I didn't want to blow it up so i torn it apart. Now i have a new cam chain and tension valve cover gasket and flywheel stator (left side engine gasket) also new head is on its way. PROBLEM- Guys at the motorsports store said valves looked good and jug looked fine along with the piston (valves were still in head and he just glanced at them). QUESTION-Do i reuse the old valves in my new head (probably not) so if i order new valves can i use the old springs with the new valves? Last question, since ill have a new head and (if need be valves,springs,locks,seals) what size shim (referring to the small metal circles under the lifters) do i use since it'll be OEM. Please get back with me asap. Thank you!!
  12. Ali S.

    2006 RMZ250 timing

    If I'm adjusting the timing on my rmz 250 and the timing is slightly or barely off, will it start? If it will would it get damaged over time or something? I just wanted to know just in case I timed it slightly wrong on accident.
  13. Otto646

    kx250f God Awful Noise KX250F

    I recently purchased a 2010 KX250F from a friend of mine that had been sitting in his garage for about 5 years. The bike seemed to be in decent shape and the price was right so i picked it up. I went through most of the bike before riding it (air filter, oil, greased all the bearings, adjusted suspension, changed all the fluids, etc) The valves sounded a bit loose so i decided to have a "Buddy of mine" adjust the valves. I get the bike back, go for a ride and the cam chain tensioner falls out while i was riding, luckily i caught it very soon after it happened and it never jumped timing. I put the tensioner back in and continue to ride the rest of the day. as the day goes on the valves sound much looser than they were originally before the adjustment was done, I decided to call it a day and tear the bike down myself. I shim the loose valves and button the bike back up, but now the thing sounds god awful. Straight up clacking coming from the right side of the top end. Since then ive probably had the bike apart and back together 4 or 5 times trying to figure out the problem. Its not the auto decompression valve, every valve is in spec, timing is solid, and the cam chain tensioner is working fine. I'm stumped. anyone have any thoughts?
  14. Just finished adjusting the valves on my 2008 crf250r, I kicked once and the motor turned over maybe one rotation and then it locked up. I thought the cam was set correctly but it' possible its off. I also forgot to use the engine locking bolt on the bottom side that locks it at tdc while working on it but I wasn' concerned because I didn' feel like I was turning the engine the chain while working on it. Before the valve adjustment it kicked over fine. What could the issue be?
  15. billy400cc

    cam timing off. 2003 DRZ400s

    How do I fix this mess I've gotten myself into? I was adjusting valves and turned the engine over without the cam chain tensioner in place and ended up with the arrows at 11:30 and not 12:00. The bike is at TDC compression stroke. I am in the 15th pin though.
  16. FatCowKiller

    Cam timing and clattering

    I have recently done a lot of maintenance to my WR 450f and there are still some issues which concern me with it, when I took out the clutch basket there was a gear with a bent piece on it (picture attached) This was probably done by the previous owner but I think it should probably be replaced? - When I checked the valves they were only opened for measuring when the knob things were pointed down instead of up, (picture attached) I dont know if the timing is messed up or if it has been retarded to the yz specs. ( the picture of the cam chain was when the valves were open, at the same time as the knob things were downwards in the other picture). -There is also a clattering noise from the engine but it seems to run fine? I will try to make a video for mine soon but it sounds pretty much like this persons - sorry about the bad pictures.
  17. OffRoadEmpire

    sparkissue Ktm 300 2012 no spark

    Hi guys I took of my stator cover and starter. i Put everything back together in correct order but no spark dont know if there are any wires that could have pulled out or disconected Please if any body has an idea or know of anything i can look at it would be much appreciated.. Kind Regards. Clueless
  18. Hi everyone, I have a new-to-me 2005 CRF230F. This forum has helped me several times in the last couple months, but I created an account this time as I was unable to find an answer to this question: I removed the timing hole cap and crankshaft hole cap. The problem I'm having is as I approach the T timing mark by rotating the crankshaft counterclockwise, it spins right past it. I go by the F mark and then about 1/2 or 3/4 of a inch before the line to the left of the T would be lined up, it spins right past. I tried using a screw driver with the socket on the end instead of a ratchet so that I could try to hold it on the T. I am able to do that, but as soon as I release pressure, it spins past. Any help would be appreciated.
  19. Alright, so I just got done rebuilding the top end on my 07 KX 450F and as I am getting ready to install the top of the cylinder head I notice I have one last piece remaining that I can't account for. I mark everything and take several pictures so I can make sure everything is put back together perfectly, but somehow this piece evaded me. I showed where I think it goes in one of the pictures I provided. Can someone tell me if I am right or if this piece goes somewhere completely different?
  20. Jdur8093

    Rm125 timing

    HI guys, last post recieved great help so hoping the same here, basically I think I’m experiencing some timing issues on my 02 rm125. The timing marks on the magneto were slightly out by like a degree or less, in favour of an earlier spark, worried that I was gunna fry the piston, I moved the timing marks by a degree in favour of a later spark just for piece of mind that I wasn’t harming my freshly rebuilt engine, since doing this o think I can hear the bike ‘pinging’ when riding at a steady speed, and has developed a ticking noise from the top end, it runs okay maybe a little splutter before the valve opens and possibly down on power a little but I ride a sports bike so maybe it’s just not that fast compared, but once it’s cleared out it sings through the gears as it should, can anyone help? Will post a picture of current position on magneto, also I haven’t proper tool for measuring tdc but by feel on the fly wheel this is pretty much where it’s at, that can’t be right considering the crank turns anti clockwise?
  21. I just finished rebuilding the top end on my 2001 wr250f. The bike has an Athena 290 big bore cylinder and piston. I never checked the valve clearance before the rebuild. After rebuilding, I checked the valve clearances. All three intake valves have zero clearance. I cannot get my .03mm gauge to slide in. The exhaust valves are only slightly on the tight side with .015mm each. I double checked and made sure I wasn't on the exhaust stroke. I have zero clearance on all valves on the exhaust stroke. I even tried turned the flywheel back and forth from TDC and measuring to see if my timing was off, causing the zero clearance. These test also had zero clearance on the intake valves. Have all three of my intake valves worn down to the point where there is no clearance? When I had the head off, the bottom of the valves looked decent. Slightly blackened, with a small amount of carbon, but I didnt notice any major wear, chips or cracks. Anyone got any idea what's going on here? Thanks in advance for your guys' wisdom.
  22. Timing, they say, is everything, and that’s particularly true with engines. Understanding how and when the individual events happen, and why they happen when they do will help you understand why they have to be set up as they are, and that always makes it easier to figure out what’s going on when problems arise. Let’s start by going over the basic way the engine works, and what events need to occur and when. First, we’ll look at the simple basics, then at the reason things happen exactly when they do. To simplify the discussion, and to make it more closely relevant to dirt bikes, we are only going to discuss single cylinder engines during this explanation. The term, “four-stroke cycle” means that the engine needs to move the piston up or down the bore 4 times to complete all the functions that go into producing power from gasoline. Because the piston is connected to the crank via the connecting rod, each “stroke” takes a half revolution of the crank, or two full revolutions for the four necessary strokes. The Four-Stroke Cycle A lot of folks have seen this simplified version, but let's review. The cycle starts with the Intake Stroke, near top dead center (TDC), where the piston is at its highest possible position, with the intake valve opening and the piston moving down the bore toward bottom dead center (BDC). This creates a void above the piston that is filled by air from outside rushing in through the intake port to fill it, and that air carries with it the fuel added by either the carburetor or a fuel injection system. The rotating crank then begins to move the piston up the bore and the intake valve closes, trapping the fuel and air in the cylinder. As the piston continues upward, the air/fuel mix is compressed, which heats it and increases the amount of force with which it will expand when ignited. This is the compression stroke. The power stroke begins near the top of that second stroke, when ignition takes place, starting the fire. The crank rotates past TDC as the burning fuel begins to expand, and the combustion force pushes the piston down the bore, creating the rotating force on the crank that drives the whole works. As the piston nears BDC again, the exhaust valve opens, and the piston is run up the bore to pump the spent gasses out through the exhaust port to complete the cycle with the exhaust stroke. Half Speed Notice something here: The engine’s crankshaft rotated twice to produce four trips up and down the cylinder for the piston, but each valve only opened and closed once during that time. To make this work, the camshafts have to turn at one half the engine speed, so the chain and sprockets, or gears, or toothed belt and sprockets used to drive them are set up at a 2:1 ratio. Ignition also has to happen right on time, so each ignition system, whether simple ‘50’s style points, or the most sophisticated electronic, has to have something to signal when that is. Traditionally, this signaling trigger has been attached to the camshaft so that the spark occurred only once every other revolution, but engineers seeking to simplify the design of single cylinder dirt bikes found no reason that there could not be a spark on every revolution, so the trigger sensor was mounted at the crankshaft instead. That means there is a spark on every revolution, instead of only once per each two-revolution cycle of the engine. The second spark happens at the end of the exhaust stroke, so there’s nothing present in the cylinder that would burn. It also makes setting up the timing during assembly somewhat simpler by eliminating what used to be a common mechanic’s mistake of picking the wrong top dead center position. Getting Ahead of Things (The Engine is Dynamic) Simplified explanations of the cycle like the one we started with here always show the valves opening and closing right at TDC and BDC, but if you watch the piston position as you turn an engine over by hand to watch the valve gear operate, you will notice that the valves don’t open and close at the exact top and bottom of their respective strokes. That’s because the engine is a dynamic system, which means it’s something that moves, and it does so at a pretty high speed. Most MX 450’s make peak power at around 9000 RPM, which means they make two full revolutions and complete an operating cycle in about 13 milliseconds at that speed. The crank spins continuously, but the intake, exhaust, and combustion all stop and start again while that’s going on. That means that all of these events actually have only a certain amount of time in which to occur, so they have to be started in advance so that they happen on time. Again, we’ll look at the intake stroke first. With the crankshaft spinning along at a few thousand revolutions per minute, if we were to wait until top dead center to open the intake valve, the piston will travel well down in the bore by the time the valve is open wide enough to let much air into the cylinder, so the intake valve begins to open around 20 degrees or more before top dead center (BTDC). This does a couple of things. For one, the exhaust stroke is just ending, and the inertia of the spent gasses leaving the cylinder creates a bit of a vacuum that helps get the intake air moving in. There’s a little bit of built up pressure right behind the intake valve as a result of the intake valve having been slammed shut on a moving column of air at the end of the previous intake stroke, and that helps, too. But mainly, we want the intake valve to have time to be open nice and wide as the piston moves through the fastest part of its down stroke so we can get the cylinder as full as possible. On top of that, we’re going to keep the intake valve open until well after bottom dead center (ABDC) to take advantage of the inertia of the incoming air. Which brings us to the compression stroke. The piston is now rising and pushing against the load of incoming air, stalling the flow into the cylinder, so the intake valve closes as this balance is struck, about 130 degrees BTDC. With both valves now closed, the piston compresses the air and fuel mix to less than 1/10th its original volume to heat it up and to increase the force with which it expands as it burns. This compression will continue until TDC, but the ignition has to happen well before that in order to extract the maximum power from the burning of fuel. The Power stroke, then, is initiated before the piston actually starts down. This “spark advance” allows the burning gasoline time to start at one small point near the spark plug and spread across the combustion chamber to the point where it becomes confined by the piston and must push it down out of the way. That’s where the power comes from. If the spark occurs too late (is “retarded”), the piston will outrun the fuel burn and not much pressure will be applied. On the other hand, if it happens too early (“advanced”) then too much pressure will be created while the piston can’t get out of the way fast enough, which leads to damage from detonation and the like. The faster the engine turns, the more advance the ignition needs to keep up, so modern systems advance the timing as the RPM increases. At about 120-130 degrees ATDC, the energy from the fuel burn is so low that it really isn’t putting a lot of force on the piston any more, and the leverage that the piston has on the crank is getting pretty low, so the exhaust valve starts open before reaching BDC. The pressure that remains from the burn starts the gasses flowing outward, boosted by the piston as it rises and pumps the bore clear. The exhaust valve remains open past TDC to utilize gas inertia and help restart the intake airflow for the next cycle. Am I 180 Out? People ask this a lot when they have trouble getting an engine running after they’ve set the cam timing up, or when they bring the piston up to Top Dead Center and find both valves open. This is the common mistake we mentioned earlier, and it's one of the things that's more easily understood when you have a good grasp of the complete cycle. It’s more of a car thing, but if you have an old classic four-stroke from the ‘70’s or before that uses cam driven breaker points, it’s sometimes possible. These days, the answer is usually, “no.” The old way of connecting the ignition to the engine mechanically, that of using a distributor or some other device driven at half speed by the cam, allows a mistake in assembly to be made. A mechanic could position the engine at TDC, and if not careful to check, he could position the ignition trigger to fire during the exhaust stroke instead of the compression stroke. This was referred to as being “180 degrees out” because the distributor or point plate was 180 degrees away from the correct position on the camshaft because of this. Actually, going by the crank, the ignition timing was 360 degrees out. But with the ignition trigger located on the crankshaft instead, as is the case with virtually all modern single cylinder dirt bike 4 strokes, that’s not possible. Without the cams connected to the crank, one TDC is exactly like another; the rod’s at the top, and the spark signal is given as the crank gets there, every time. So, the only thing that determines which stroke is which is the camshaft(s), and how they are positioned by the assembler. That’s why the service manuals for such engines make no mention of checking for which of the two different TDC’s is used. In operation, there is a second, "wasted" spark that happens near the end of the exhaust stroke. What About Automatic Decompression? This is another area where really understanding the four-stroke cycle helps clear things up. It's extremely common to hear people tell someone with a modern four-stroke single to "find TDC" before starting, but that's wrong. When you turn the engine over slowly, you find it rotates fairly easily until you come to a "hard spot". Without auto decompression, the hard spot is the point at which the intake valve closes to begin the compression stroke. That looks like the picture below, "Non AD". From this point, you would need to force the engine to compress about 80% of it's full stroke length worth of air, and that can be nearly impossible with the high compression ratios used these days. What automatic decompression does is use a speed sensitive mechanical system to lift the exhaust valve off its seat at very low speeds (slower than the engine will idle at) until the engine gets a lot closer to TDC, but not past it, so that when kicked over from this position (or spun through it by a starter motor) there will still be enough compression to start, and both valves will be closed as the spark happens and the end passes top dead center. That looks like the "Auto Decomp" picture above. You can see that there will be a lot less effort needed to compress the air/fuel charge from here than from the normal, non auto decompression setup. This, by the way, is where you want to be if you have an older manual decompression engine. If you go past TDC instead of stopping just prior to it, you would have to kick the engine through nearly two full revolutions to get back to the compression stroke again, and it would still be at full strength. Once you have the whole picture set in your mind, you'll make fewer assembly mistakes, and you'll be able to catch on to problems more quickly. A crusty old mechanic told me a long time ago, "The best way to figure out why something works wrong is to know how it's works when it works right".
  23. I've tried adjusting my accelerator pump so the squirt just barely hits the slide. The best I've been able to accomplish is the squirt starting as the slide is half way up, this is with the adjustment screw back out all the way. The original setting was 4.25 turn out and at that setting the squirt started once the slide was almost all the way up. I recorded the different setting with my phone and went frame by frame to check. I can't seem to figure out how to post a video with slow-mo to show what I am seeing. From what I've read I should be able to back the adjustment screw out until the squirt actually hits the slide but I can't do that with my bike. I do get a fairly bad lean bog, although I haven't tested it since getting the squirt to be somewhat faster. My question is what would cause the squirt to be so delayed compared to what I've read in other bikes? Anywhere I can start trouble shooting? Thanks! (I have the stock 55 leak jet)
  24. I have this spark plug o ring left to install, and I cannot for the life of me figure out where to put it and I don't want to chance it and install it the wrong way. will someone please tell me where this thing goes.
  25. sup guys, i got a bit of a story. a few days ago i bought a 2004 crf250r for 800 bucks off a guy who didnt know much except a few things... 1. has an oil leak (shift linkage seal was half out ) 2. had a 'full rebuild' by the previous owner 3. had a hard time starting so i snatched it up, hoping it would be a quick fix. its not exactly going that way. i brought it home, cleaned out the carb, and fired up after several kicks. the idle was pretty high, but wouldn't come down without completely dying on me. so as the bike is running and im trying to get the idle down, i noticed two things; 1. the thing backfires practically every 2-3 seconds and 2. the exhaust pipe was so red-hot, it looked like it was about to turn into a damn puddle of molten metal. realizing there was something seriously wrong with the bike, i shut it off. this brings us to my first question. why in the frick is my pipe getting red hot and shooting flames after 60 seconds or running ? and whats with the back firing ? now for part 2 of story time. with a bit of research my dad's opinion, i assuming that there was some sort of problem with the exhaust valves. long story short, the exhaust valves were perfectly fine. my next thought was to check the timing. take a look at the pictures in the link below and let them speak for themselves. https://www.pinkbike.com/u/Ziggypop14/album/nothing/ as you can now see, the notch on the magneto cover does not completely match up with the notches on the flywheel. i noticed there are two notches on the flywheel, where should the notch on the cover versus the two on the flywheel? im assuming in between the two? i researched and found a few things that could be at fault. 1. the cam cog slipped on the shaft. which really cant be it since at TDC the two notches on the cam cog are still completely level, and if the cog slipped, the notches would be off. Right? 2. the flywheel slipped on the crankshaft. this one makes the most sense because how else can the flywheel notches be off while the other notches are dead on. but how the hell is that even possible? the flywheel nut is so tight that i cant even get it off to see if the keyway is still intact. (still trying to get it off, jamming sockets in gears) unless the idiot who rebuilt the bike didnt put the keyway in (which is entirely possible), i cannot see this as the solution. this brings us to my 2nd and final question. Why aren't the flywheel notches lined up even with the piston at TDC and everything else lining up ? any help is is appreciated, i need my garage back!! cheers, Riley
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