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About deweym21

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    Track Days, Touring, Sport Touring, Dirt, Supermoto

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  1. Yes you need to have the retaining washer on there so this doesn't happen again. You might get lucky and tightening it may solve your problem. it likely did some sort of damage to your seal though. Luckily you can get a countershaft seal kit pretty cheap. Why people don't use the retaining washers, chain guards, and case savers confuses me.
  2. deweym21

    1998 YZ400F right side engine noise

    It might be a rod bearing. If it is the rod bearing now is a good time to consider throwing a 426 rod on there and having your cylinder bored out and replated. Just an option. It also Sounds like something is loose potentially something like the balancing which has a nut on it that are prone to loosen up. The right side case cover rest pretty much against it which may be the only thing retaining it. When you do your tear down I'm guessing you're going to go ahead and pull the entire engine. Other than your typical top-end job make sure that you pay a specific attention to your valves for wear as well as to make sure that you're within Tolerance on your valve springs. They have gone up and down a lot of times over the years! In all reality, you just don't know until you tear it down and find the issue.
  3. deweym21

    400 to 426 conversion, the easy way

    Yes that may be better. The 05 and newer are more ideal. Sorry you're having trouble. Are you sure you have the intake cam timed normal with 14 cam chain pins between the top intake timing mark and the top exhaust timing mark? Wishing you better luck with the next carb.
  4. deweym21

    Crankcase damage. Help!

    Looks like you got a case half to buy. The clutch mechanism is exposed! Were you using a case protector? What model is this?
  5. Try a 48 or 50 pilot jet humor me
  6. https://www.oemdirtbikeparts.com/wr450f-yz450f-carb-intake-fuel-system-parts-Stock-p/wr450-03-11-yz450-carbs.htm
  7. It seems to me you're talking about the breather hose from the valve cover. This is the only engine case vent it has. it's not uncommon for it to spit a little bit of oil after a bit of riding out of this some people that ride Trail like to set these up a little higher just for the precaution of not sucking any moisture in or getting water in if they go through a puddle. My route mine into my airbox as it is used for Supermoto and I don't want any of that oil on the tarmac. Sent from my SM-G900V using ThumperTalk mobile app
  8. I used the Pro X rebuild kit for my old 400 with the original carburetor. I liked everything about it except their quick turn mixture screw. It had 4 settings on it and it never actually seemed to be seated correctly. I replaced it quickly with the stock mixture screw which is a pain to get to but it stays put. I think that you should check valve clearances. Rocky mountain ATV/MC has a good youtube video on the how to. When you do this procedure, make sure and get the decompression mechanism placed properly so that the mechanism doesn't get hung up and your spring is in the correct position. If this is going to be a long term bike, I suggest getting a shim kit for your adjustments. Hopefully your local powersports store has them in stock so you can have them and not watch for the parcel carrier. If you need any other help, reply here or inbox me.
  9. I know these engines are pretty high strung. I would recommend you refer to your manual as to the service interval for the piston and rings. I have trust issues with shops so I do my own stuff on my bikes. It's important to service your piston an rings because when they wear out they will in turn wear out your cylinder and that will cost you more. I recently fixed a friend's bike that was supposedly out of shop that had no compression. They said that it probably needed a new head. After tearing it down the intake valve have no clearance and the Piston was not checked. It had the original piston in it and the ring Gap was out of spec. My advice... Get your hands dirty!
  10. Just out of curiosity, how many hours are on your top end and have your valves been checked for clearance lately?
  11. deweym21

    400 to 426 conversion, the easy way

    I think there is a thread for interchangeable parts. I would pay very close attention to the brake caliper mounting point. I thought they changed it slightly somewhere. Those fork tubes are pretty easy to service yourself if you have a few tools. If you have the carburetor for the 450, and it's in good shape, it might be a decent upgrade if you get the jetting right.
  12. deweym21

    400 to 426 conversion, the easy way

    I'm sure you have read this but the whole purpose that people initially used the exhaust cam from the 450s was because a suitable aftermarket option was not available. If you want something that you can have some real confidence in I would suggest didn't you a nice hot cam set for it. It is the same set of cams as the 426 so it works a little better for the 426 but still some notable improvements and of course the cam chain fits perfectly on it as well as your timing marks line up perfectly.
  13. deweym21

    400 to 426 conversion, the easy way

    The exhaust cam should be the only one you use. The timing marks will work for the stock cam on the intake. There should be 14 pins on the cam chain between top timing mark of the properly timed intake cam and the top mark on the 450 exhaust. The chain will work on the 400 just as well in the 426 as they are the same. The 450 chain will have a conflict with the cog on the crankshaft. The 450 intake marks will not align as the exhaust will not.
  14. You should have kept them. I'm going to send a direct message
  15. They work for the other two those are just steel I'm still interested