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By Dwight Williams
Ok, so I bought a 2006 bayou 250 for 200 bucks, kid couldn't start it and had no idea why it wouldn't run, I pulled the rope and felt what I thought was valve to piston contact, he wanted 500 and I talked him down to 200 and brought it home. Sure enough, timing was way far out, timing chain incredibly loose. So for fun I re-tensioned the timing chain and re timed it, got about 120lbs of compression, pretty low. I cannot get the chain very tight but the the tensioner seems to work fine, the chain guides don't look very worn. Also, when I took the head off the valves don't look bent and the piston has no discernible marks on it. Is this an interference engine? I sure thought I felt some contact with the pull rope but maybe no permanent damage was done? Anyway, I plan on doing a full top end job as well as timing chain tensioners and hopefully that'll cure it. Is there any reason other than chain stretch (I measured it and it's ok) or guide wear that would cause the chain to be so loose? Thanks!
I've never done this before but after reading a few thread I decided to check my valves for the first time and to my surprise it was much easier than I thought.
My bike is a 2005 Sp 500 HO.
I first pulled the seat and the right side panel off, and that's it! It wasn't too bad to get at.
Next I pulled the spark plug out and removed both the head cover ( 8-8mm bolts)
then the side cam cover (5-8mm bolts).
Also remove the plug in the recoil cover (14mm bolt) to see the timming marks.
Next I turned the engine over with the pull cord untill it was at TDC of the compression stroke.
The best was to tell that your at TDC of the compression stroke is to rotate the engine until the
timing marks are parallel to rocker cover gasket surface.
The cam sprocket locating pin will be facing upward directly in line with the crankshaft to camshaft center line.
Now fine adjust by looking into the timing hole in the recoil cover and line up the upside down "T" on
the flywheel into the center of the hole.
Now using a feeler gauge, slide the .006" (.15mm)blade between the top of the valve and the bottom of the adjuster and adjust accordingly
To adjust, Loosen the locknut (10mm) and check clearance with a feeler guage. Clearance should be .006" (.15mm) for both, intake and exhaust valves. Turn the adjuster with a stubby flat blade screwdriver untill the proper clearance is achieved then tighten the locknut (5.8-7.2 ft. lbs) while holding the adjuster in place with the screwdriver. Re-check the clearance with the feeler guage one last time and re-assemble the covers (72 in.lbs) and plugs.
The only thing that i noticed was that I had to clean and silicone the side cam cover other than that I found the whole process rather simple.
I'd give it a 4 out of 10 on the skill level scale.
I hope this helps!
By Reece Bowen
x just bought this expedition 425 and the Speedo needle does not work. The lights work for the shift indcator. So is this an electronic Speedo or cable? Is there a way to fix it or will I have to replace the unit? Thanks for any help you can provide.
By Frank Angerano
I’ve decided to post a thread on the process of cleaning a carburetor and what’s needed in order to do it properly. There are some members that are new to this and are not very versed in doing so. I want to help and feel this might explain things better. I would hope this helps you along. We all have our own little tricks of the trade so I’m sharing my process on how i break a carburetor down, clean, reassemble and adjust it to peak performance. I welcome any other members input on this topic. List of things I use: Safety glasses !!! Rags. I like to use old white Tee shirts or I buy and always have a few white pillow cases from the dollar store on hand. The cheap ones. I like to use a frisbee turned upside down like a bowl to keep the liquids to a minimum on spillage to the work bench. A set of cleaning picks and brushes or a piece of bicycle break cable, I separate the strands and use them to clean out the tiny holes in the jets. (Pic attached) A can of gum out carburetor cleaner with the small red tube that attaches to the spray tip. (Pic attached) A can of compressed air, the kind used to clean out keyboards on computers. It also has the small red tube that attaches to the spray tip. Or a compressor if you have one with a blow out tip. (Pic attached) A piece of clean hose that I can connect to the fuel line port on the carburetor to test the float operation. About 10 inches long. A few Q tips. The process: I like to put the pillow case down on the work bench and spread it out flat. This really helps in being able to keep track of parts. Especially because it’s white. I use the frisbee because it’s small enough to keep parts contained and durable enough to deal with the chemicals and any gas that will come out of the carburetor while opening it up. It’s important to make sure you keep track of where everything came off and where the screws and parts all go back. I like to start at the bottom and pull the bowl off. I immediately spray the inside of the bowl down with carb cleaner until its about half way full and set it aside. Then I take the float out and check it for any fluid inside. If it’s a white color float you can hold a flashlight under it and see through it for any fluid inside. If it black just shake it up and listen for fluid inside. No fluid inside is a good thing ! When the float comes out the fill valve needle will come with it. I take that needle and put it in the carburetor bowl that I filled with carburetor cleaner. This way it soaks for a bit. I do the same thing with the jets also once they are unscrewed and out toss them into the bowl to soak. Take the air/fuel mixture screw out and soak that as well. Side note: the air/fuel screw should have a screw, spring, washer and o ring. After all the jets and parts are out and soaking I like to take the carburetor cleaner, use the small red tube and stick it in all the little holes/ports on the carburetor and spray. I do this while it’s in the frisbee. This way there is no mess. I look to see where the spray pressure comes out on the other side of that port. Once this is all done I start running my brushes and cleaning tips gently through all of the holes/ports and spraying it again with the carb cleaner. After I feel I’ve seen a clear flow of fluid through all the openings I spray them with the can of air the exact way I did with the carburetor cleaner. This will blow out any left over junk that’s still in the carburetor. Check the choke operation is working properly and spray it clean. Most choke devices are easily cleaned up so hit it and move on since they are mechanical and it’s just a matter of freeing them up, spraying with cleaner and lube. There are multiple types of chokes but many of them for the most part are mechanically operated. Once this is completed I wipe the entire carburetor down good and blow it clean and set aside. I then start working on the jets one by one. Start by running the cleaning tips and brushes through all the tiny holes making sure they are all clean. Hit it with the carburetor cleaner and then air. I hold a flashlight to it when it’s done so I can make sure all of the holes are clear. I set all the jets aside on the work area. Do the same thing for the float needle and air/fuel screw. Now once this is all complete you can set the frisbee aside and start to reassemble the carburetor on the clean white surface. I start by running a Q tip in where the fill needle sits into the carburetor. Some carbs have a small o ring that needs to be clean for proper seating of the fill needle. Carefully reinstall the jets where they came from and do not strip or over tighten the jets and use the proper size screwdrivers when removing and reinstalling the jets. Reinstall the air/fuel mixture screw and set it to what’s called out in the manual for that bike. Install the float and fill needle assembly. Now in order to test that float I like to take that piece of hose I mentioned and connect it to where the fuel line gets connected to the carburetor. I then turn the carburetor over to the upright position and blow into the hose. You should hear air coming out of the bottom of the carburetor. While blowing, lift the float up and the air should stop. Let it go and the float should fall down opening the fill valve and you should hear air again. The air should stop about 3/4 way up when raising that float while your blowing air into it. If so then your good to go. If not make an adjustment Set the carburetor down, take the bowl and empty it. Clean it out and scrape/wipe any old junk inside and blow it out good. There is a screw on the outside of the bottom of the bowl. Remove it and clean it out and reinstall. Turn the carburetor over and reinstall the bowl. Tighten the screws in a crisscross pattern so the bowl seats evenly. I like to put the hose on one more time and do a float test to make sure it’s opening and closing properly. All you have to do is blow into the hose and run the carburetor upside down to see if the air stops. Reinstall the carb and you should be good to go! All pics of the items I use are attached below. If you understand this great. If not ask away! Don’t be shy and don’t cut corners. You will only wind up pulling the carburetor off of the bike for the third and forth time before you get it right. The last thing to be discussed is dialing in the air/fuel screw when your finally put back together and running. This is a relatively easy task. Again I hope this helps! Frank.
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The Hop-Up: You may be saying to yourself, “that’s a chick bike,” and you’re right. But honestly, it’s so much more than that. It’s one badass bike. http://www.quadmagazine.com/quad/features/article/0,24942,1587044,00.html
Hi all, I try to find this manual in the threads but you have a lot of stock here
Cannot find this particular manual.
I found it for YFM200 but not sure if they are the same.
Thanks if you could help me with that.
Im new here so if I did something wrong, please tell me.
i was wondering if i could get some help. i been trying to locate where the fuel and air adjustment screws are located on my 95 kodiak 400. i think i found the fuel screw.. i know where the throttle adjuster is but i cant find the air screw. or is there an air adjustment on these carbs?
looking for direct shift shifting lever that properly fits my 2003 Yamaha warrior 350 and fits my foot the same as a stock 2003 Yamaha warrior 350 shifting lever fits my foot
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