Idahoyamahauler

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About Idahoyamahauler

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    Idaho
  1. Lmao Lots of freshly rebuilt and low hours stuff on craigslist. Few people would argue that Yamaha four stroke‘s are the most reliable But that is assuming you are comparing a new Yamaha to a new “you decide” There are lots of people rebuilding four strokes these days that shouldn’t be you are rolling the dice with anything used Unless you know the bike Personally I would find one that will allow me to put the most amount into my rebuild If you are not up to the rebuild yourself (Obviously you don’t have the budget for a shop rebuild ) Find something you like that sounds good and feels strong But pull the head and check all the valve-train. check all the clearances, replace the chain, make sure all the valves are sealing Yamaha‘s have the best service manual also, and explain all of this. Good luck on your dice
  2. Those are definitely nice bikes. And EFI is absolutely the way to go especially if you change elevation much like I do..... I have a 2012 yz 450 and ride from 3000-9000 All I ever adjust is idle speed just a little FYI if you don’t already know.... wear parts Like the chain guides and sliders are very good indicators of time especially if they are stock and they usually are. Good luck
  3. https://en.wikipedia.org/wiki/Torque-to-yield_fastener
  4. They do it this way because torquing becomes less accurate at higher “tighter “ values By stopping at 14 you know the torque is consistent but to make sure the head remains perfectly flat to the jug you finish by turning them all the exact same amount, or “degrees” The bolts have six points 360° divided by six Means each point is 60° To get 90° turn the bolt 1-1/2 points
  5. Negatory. it’s not going to run fine if the bowl can’t stay full of fuel. I admit electrical issues are probably more common but if the plug is dry no matter what.... what does that tell you ? Pretty much anything I have ever seen that had a spark problem would be fouling plugs Jmho
  6. It takes more fuel to run faster If the bowl can’t stay full because of a lack of supply... they can act like the floats are not set properly. As I said. Not common But I’ve seen it.
  7. I asked before if you have verified fuel delivery. It’s not a common issue but... if the petcock or line is partly plugged.you can get a slow run situation.
  8. Sort of sounds insufficient fuel Id check the petcock and verify good fuel flow. I would tell you to check floats and needle but you said that all checks out...
  9. Mint engine now you're talking. You have a head that looks like it belongs on Frankenstein. Now we don't build based on looks . However we also know that it is on its 2nd go already and grenaded. You say all valves are bent. Want a mint head for your mint engine ? It needs all new guides and seats. Guess what ? For slightly more dough ( maybe less ) you can buy a complete head. Brand new and ready for brand new valves. You already know your buying cases, crank and I would hope all new bearings. If you salvage oil pump water pump and gears you're already going to be into about grand probably 1500. I assume you plan on a new jug and piston. There's another 4-500. MAYBE cam can be used But that is another absolutely critical part of the valve train. It has got to be professionally inspected For timing or all of this $$ and work is a time bomb again. With all that is it worth it to try to save a couple Hun on the head ? These things are not tinker toys They are as I call them " finely tuned pieces of bad a-- !! ". They rotate at 200 times per second ! Valves open and close 100 times per second !!! Everything needs to be near perfect. Parts and labor Just my humble opinion.
  10. Bro, You need a new engine ! That "motor" IS JUNKED !! I would not even consider putting any of those parts, except maybe the tranny gears back into a rebuild. You do not spend good money and time rebuilding an engine and use parts like that. Especially the head!!! Most of the catastrophic problems seen in modern high revving four strokes are valve related. Either from poor maintenance or lack of maintenance. Shop around and you can probably find a new complete head for less than you will properly rebuild that one
  11. Just for future reference.. Metric tire sizes seem confusing . But are actually very simple and usually offer more choices First number is tread width in mm . The second number is a percentage of the first and refers to the height of the sidewall, again in mm The third number obviously is rim size in inches which is why a lot of people get confused . So a 120/90 tells you The tread is 120 mm / sidewall is 90% of 120 or 108mm. When you understand the numbers it allows you to change the width with or without changing tire overall height. There can be a little variation in actual tread width between manufactures and or tire model . And of course rim width . A narrower rim will "roll up " The tire a little more making it look and feel rounder and vice versa .
  12. I don't know how fast you were running it when it went.... But s--t don't stop right away.... Those valves can be opening and closing 50 times per second Once one piece goes all bets are off
  13. Did it jump time ? Or did you not check before you tore it down ?
  14. At first glance it looks like you lost a keeper on that valve . Did you peen the stems to make sure that does not happen ?
  15. Reverence nailed it when he said A large amount of material needs to be removed before welding for it to be ANYWHERE CLOSE to what it was . The forces in play on some parts cannot be simply stated with a number. Sorry to say it but if you value your life and want peace of mind... Replace it .