tt decompression plug ??

5 replies to this topic
  • 800screws

Posted July 26, 2005 - 04:47 PM


is the gasket supposed to fit inside the decomp hole and then the screw with the copper washer holds the plug in where the lathed part of the plug is? right? how to u get the plug in. it seems like the gasket is too big? any tricks?
also how do u tighten up the cam chain tensioner? i read in the manual what to do, but mine doesn't move a milimeter. could it be stuck? how do u loosen it?
lastly, what's the word on the dr.d wet sump conversion for an 02 426? good, bad, not worth it? anyone use it?
thanks for all your help!

  • grayracer513

Posted July 26, 2005 - 07:07 PM


There's no gasket. It's a seal. If you just took out the old manual decomp shaft and didn't remove the seal, you can probably reuse that unless it was damaged in the removal of the shaft. If you are going to use the old seal, just put the plug in with nothing else on it. Eyeball it with a flashlight to be sure the retention groove in the plug shaft is lined up with the bolt hole. The bolt should run all the way in by hand, or very easily. Be sure it's lined up, or you will strip the threads. Don't overtighten it, either.

If you want to replace the seal with the new one, be advised that the OEM seal is tough to remove. Don't butcher the hole digging it out. You should be able to remove it by prying it out with a screwdriver. Just be careful.

Once it's out, put the new seal on the plug, not in the head, with the lip facing the inside of the engine. Push the seal and plug as far in as you can get it by hand, then take a good sized pair of channel lock pliers and put one jaw on top of the plug, and the other on the end of the cast boss on the head that the plug fits into. Squeeze the plug into place, eyeball the bolt as above, and lock it down.

The cam chain tensioner is completely automatic, and steplessly removes any slack it finds up to a preset level of tension. They require no adjustment. The only time it's necessary to mess with them is if you are going to disengage it so that you can remove the cam chain, as when you adjust your valves. When you're done, you simply unload it, and it's back on the job. It's a brilliantly simple and robust design.

Wet sump conversions are race only, find the last little tiny edge kind of things, and have no practical use on anything other than the most serious race bike, if even then. They reduce the oil supply, making it necessary to constantly check the level, and change oil daily. Kind of like a Honda. Not for me, thanks.

  • 800screws

Posted July 27, 2005 - 02:56 AM


thanks, u answered all my questions, except that the cam chain tensioner wont wind up to reinstall it. and it won't go in flush without it wound. the manual says press on the end and wind with a screwdriver, but mine doesn't do a thing when i do that.

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  • Daz_426_02

Posted July 27, 2005 - 04:29 AM


Hahaha nice answer Grayracer !! (Honda) :applause: :) :eek:

800screws, apply light pressure (by hand) on the part of the tentioner that goes into the motor and turn the screw in the back of the tentioner in a clockwise direction (tightening). If it is stuck it might be fully tightened, try give it a bit of persuasion with loosening it...Then when you take out the screwdriver it should feed back out smoothly... If not Replace it.

  • grayracer513

Posted July 27, 2005 - 10:46 AM


Actually, if you wind it all the way back, it will stay there by itself; a very convenient feature. Then, after installing it, you simply give it a little twist counterclockwise, and the spring takes over again. Just don't forget to do that.

  • Vibeguy

Posted July 27, 2005 - 11:13 AM


To add to Greyracer's comments, I would either safety wire or loctite the retention screw.

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