She's BACK!!!!!>>>>>>

4 replies to this topic
  • G-Man

Posted February 07, 2002 - 10:41 PM


Five gear's, four bearings a new clutch assy, plus some new rings and the mighty 426 is back. Could have got by with just replacing the damaged parts, but I might havta hang on her for another yr or so. So I replaced gears that had some wear on the dogs.

Damaged Parts:
4th pinion gear had a tooth completely sheared off.

Ring gear that is attached to the clutch assy, must have caught some metal floating around and chipped. The primary gear it rides off of had some slight damage also.

Many of the dogs on the gears showed a lot of wear for a 15 mo. old machine. This is not due to lack of oil change maintenance as I have changed the Yami-lube (non-synthetic) pretty regular. I also use the clutch 95% of the time. The only thing I figure is on practice days I tend to do long 45-55 min motos and maybe this contributed to the extra wear???

The piston rings were also past their limit.

I have decided to try the Mobil One 10-50 car oil. My mechanic friend swears by it. He also has stated that the tremedous torque loads the big thumper puts out on essentially YZ two stroke gears contributes to this.

Anyone else had there lower end apart and found there gears worn after a yr or so?

btw tested it down the street and the trans felt great and with the new rings, it felt like it had more compression. Can't wait for this weekend!

Props go out to Dano and Chad at Town & Country Motorsports as I had multiple parts orders and they got everything right and timely. Greg Geonetta also helped as he was experienced with rebuilding 4-strokes (my 1st!) and did most of the motor work. Kelly Byrd also gave some excellant advise with his previous roadracing experience rebuiding his race bikes.


  • RacerX

Posted February 08, 2002 - 04:24 AM


I still think the problem was a loose nut above the cylinder head!

Hey G, are you going to the Old Timers race this weekend? My son and I will be out there watching the OTer's and the 4 Stoke National guys tear it up.

Glad to hear you got the blue beast back together, your 15 months of riding on your bike is like a lifetime on mine as much as your ride - see "envy" in the dictionary...


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  • YZ400Court

Posted February 08, 2002 - 04:47 AM


Glad to hear you got it back together. I ordered my parts at least a week before your first post and I am still waiting :) They tell me one gear is backordered till 2/21. I hope I can remember where all these parts go :D

  • G-Man

Posted February 08, 2002 - 08:15 AM


"I still think the problem was a loose nut above the cylinder head!"

LOL yea your probably right on that one!!!

Yes I plan to race both days, look foward to seeing you and Dan. Hope your therapy is getting better.


Damn that sucks with the back order and I know what you mean when you say "I hope I remember where everything goes"!! Good luck and follow the manual closely, it also helps if you have a friend who can help you.

[ February 08, 2002: Message edited by: G-Man ]

  • YZ400Court

Posted February 08, 2002 - 01:25 PM


I have a friend that let me borrow his shimy new XR 650 today....whoaaa what a big beast. It was nice to ride again. Good luck this weekend.

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