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herm5877

YZ426F cam replacement

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Is the exhaust cam upgrade worth the cash? Will the auto-decomp. do away with the lever on the bars? Will I need the installation kit. it adds $125.00 and can this cam be put in without it? Also, is the acc. pump cover a good upgrade too, the makers of them say alot about what all this part will do, but are they just selling parts? Any help will be welcomed as I have just bought this bike and don't know more than what I see on the web. It runs great & rides great too,I just plan on some upgrades and want to spend wisely.

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I put in the Hot Cam's exhaust cam and love it. Mine start's on the first kick every time even if it has been sitting for a week. I didn't use the installation kit. All I did was put it in and then checked the valve clearances then went to the dealer and got the correct size of valve shims. You then can get rid of the decomp. lever but you will need to put a plug into it's place that you can get at the TT store. I haven't put the acc. pump cover upgrade on my bike and I have a 2000 426. I don't see the need for it cause I don't have a bog when I give it full throttle.

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The plug you mentioned is no longer sold at TT. You can find them on eBay, though, or you can cut the inboard, half-round extension off of the decomp shaft, cut the lever off of it, and use that, or, use an 18mm "freeze plug" (expansion plug) from an auto parts store.

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I put in the Hot Cam's exhaust cam and love it. Mine start's on the first kick every time even if it has been sitting for a week. I didn't use the installation kit. All I did was put it in and then checked the valve clearances then went to the dealer and got the correct size of valve shims. You then can get rid of the decomp. lever but you will need to put a plug into it's place that you can get at the TT store. I haven't put the acc. pump cover upgrade on my bike and I have a 2000 426. I don't see the need for it cause I don't have a bog when I give it full throttle.

I also did the cam swap with out a kit. I bought the oem cam. It was my first experience with the yz motor and was not hard at all. Get your tools together, and do it...totally worth it.

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I put a hotcam cam in mine as well but didn't put in a plug. I took off the lever but left the old shaft in place. The spring keeps the decomp from working. I suppose some might think it looks better to remove it and use a plug but mechanically it doesn't matter.

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I put a hotcam cam in mine as well but didn't put in a plug. I took off the lever but left the old shaft in place. The spring keeps the decomp from working. I suppose some might think it looks better to remove it and use a plug but mechanically it doesn't matter.

I did that as well but I was told by I think grey that it can eventually get in the way of shimming valves. I just took mine out last night and used a 18mm freeze plug to cork it up.

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I did that as well but I was told by I think grey that it can eventually get in the way of shimming valves. I just took mine out last night and used a 18mm freeze plug to cork it up.

Thats why you cut off the half moon shaped lobe that goes over the shim bucket.

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Thats why you cut off the half moon shaped lobe that goes over the shim bucket.
In fact, if you use your imagination, you can make a fairly good looking "plug" out of the original shaft.

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Ill be doing this shortly when my cam arrives. Just picked a brand new cam up off of ebay for 30 dollars. So I am ahead in price wise so far.

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The 450 cam or any auto decomp cam is money well spent on a 426 for sure. I had an OEM YZ 450 cam in my old 00 and I felt like it was the best mod I had done to my bike dollar for dollar. I wouldn't waste money on an install kit- just check the clearances with the new cam in and get the proper shims from your dealer. My dealer even took my old shims and swapped them for what I needed at no charge.

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If it cost 250 it would still be worth it, i did mine as soon as i discovered the 03 cam would fit, 5 years on the same cam without a single problem...

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