Dumb auto-decompression question.

I just received my exhaust cam for my 2000 YZF426. My buddy from England is going to install it for me since he gets bored while I'm at work plus he's a motorcycle mechanic. After it's installed, do we need to disconnect the existing decompression set-up?

yep, you can remove it completely and replace the stock plug in the head with one from the TT store so theres no chance of a 'blow out'.

You CAN remove the original decomp shaft, etc., But you don't NEED to. However, if you decide to leave it, and you disconnect the cable, be certain that the return spring remains in place on the shaft to keep it from engaging the compresion release randomly and damaging the engine. Also be aware that the shaft will need to be withdrawn at least partially in order to reshim the right exhaust valve.

If you have no desire to save the old shaft, you can also grind off the half round extension that over hangs the cam follower so that it can't lift the exhaust valve any more, and then cut off the arm.

The TT plug is much cleaner.

It looks cool having a 426 without the decomp lever hanging there..:naughty:

Get rid of everything to do with the manual decomp system and install the TT decomp plug.

Did anyone have to buy shims for the valve or know if that's common? Thanks in advance.

Sylvain just installed a YZ450 cam in his 02WR426 and He thought about leaving the entire stock system in place so he could still flush the engine in case of a flooded engine...

But he swears the bike now starts as easy as a IT175 (his son's bike). That's cool! I don't know if he's gonna remove the stock system or not....

Math,

Are you surfing on TT while you work ??

Shame on you if you do :naughty:

Sylvain just installed a YZ450 cam in his 02WR426 and He thought about leaving the entire stock system in place so he could still flush the engine in case of a flooded engine...

I thought the same thing. Just remove it, it's nice not having that lever up on the bars.

Only have a look at TT a couple of times during the day but Yes I do. Don't worry... I always make sure I'm ahead on the schedule :naughty:

Spend one hour reading cell biology papers... you'll see that you'll need to find something else to talk about for the following minutes...

Usually the beat is: 50 minutes of reading (scientific papers or microscope slides...) and 5-10 minutes off. Pretty much like a student or a teacher.

By the way Sylvain, I don't think I'm the only one :naughty:

Math

I ordered the TT plug and am ordering my shims tomorrow.

You can try to buy your shims from HotCams. Indy just said that you can buy an whole set of shims ( all sizes with three of each sizes) for about $60. I think it is a deal compared to the price at the dealer (at least here in Quebec.)

You can try to buy your shims from HotCams. Indy just said that you can buy an whole set of shims ( all sizes with three of each sizes) for about $60. I think it is a deal compared to the price at the dealer (at least here in Quebec.)

A guy at my local dealer can order me the two that I need for $6.00 each but having a whole set is a descent idea. I need a tire soon so I better just buy the 2.

I think keeping the comp release is worth it. I did on my 02 WR426, and I use it for a cold start-up - makes it a one-kick affair (I have a bad back and kicking is a problem). A couple of twists, choke on, one or two slow kicks through with comp release used, set it for just past tdc and it fires first time. Tip over hot flooding - pull hot start, kick through a bunch of times with comp release on, then fire it up.

I was basically raised on four strokes with compression releases. I'm very comfortable with them, and I know every trick you can pull with them. Before I bought my 450, one of the reasons I was thinking of a 426 instead was the lack of a CR on the 450, and I even researched whether one can be backfitted (it can, BTW). Now, I can't think of why I should have one, and I don't miss it a bit.

SPUTTER, I think you'd be pleasantly surprised if you just removed the comp release. It's probably easier to kick with the auto decomp cam than with the comp release pulled, but to each his own.

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