2002 Yamaha YZ426F cam change

I have a 2002 YZ426F and have read a lot of the old postings on the exhaust cam change. I am looking for any new replies and also trying to find out if it matters or not if I have Titanium Valves. And for sure if they will require shimming. any and all newer info and photos would be great.

Thanks! Keg6262 :thumbsup:

I have a 2002 YZ426F and have read a lot of the old postings on the exhaust cam change. I am looking for any new replies and also trying to find out if it matters or not if I have Titanium Valves. And for sure if they will require shimming. any and all newer info and photos would be great.

Thanks! Keg6262 :thumbsup:

I have an 02 myself.I did the 450 cam swap about 9 months ago.It was much better,a lot different.And i had to re-shim the valves,i think most people need to re-shim them.Mine has TI valves too,not had any problems as yet.

Thanks for the reply! Did you us a Hot Cam or a Yamaha Cam? I found a New Yamaha Cam on Ebay for $105.00 Not sure what one to use

I also just did the mod about a month ago. I ordered my cam from North County Yamaha for $99. I had to reshim but it wasnt way off like I expected. The only thing I had trouble with was timing triple check it before you go back together and you should be fine.

the valve type does not matter. The cam mod will work on all 98-02 YZF 400-426. Like stated ....make sure you triple check the timing of the cams before you decide to fire it up.

I did the 450 DCM in June 2003 and I used the Yamaha exhaust cam with no problems. Satch helped me out through phone calls. P.M's and emails; super guy that Satch! I actually didn't have to reshim, just the luck of the draw.

No problems at all with the cam chain or related hardware. I noticed an improvement in response across the range. Subsequent valve lash checks have shown no abnormal wear of the chain or cam sprocket as well as shimming requirements. The ease of starting is the biggest bonus. I'd do this mod in a heart beat, again. P.M. me if you want any help or to discuss this mod.

Bill

Bill,

I was going through pictures when reorganizing my computer HD and man.......I miss that YZ426F!!! :thumbsup:

92933f48.jpg

Good Ol' #9.... :thumbsup:

Thanks !!! Everyone for the replies. I'm going to order today and go for it.

Let ya know the out come when I'm done.

Who's got a link to the PDF file for him?

It's certainly a fantastic mod that I wish I had done years prior. Zero issues since my install last summer.

Ordered all my parts last week , should be in this week. However after reviewing the valve adjustments I checked all my filler gauges and found out none of mine match the books mm numbers. the book on the exhaust stats 0.0079-0.0098in or 0.20-0.25mm all my valve gauges start w a (.) not a number. I checked the clearance anyways and a .008in/.203mm fits snug. is there a difference in bike gauges and auto? of am I not understanding.

thanks.

I just did this swap on Friday and used my set of of auto gauges. Worked just fine considering I was shooting for a "range" and not an exact fit. I ended up going from 185 to 205 shims and that kept me right about perfect according to my guages, .229 mm

thanks for the reply. How did you determine your shims without the right gauge numbers?

Those shim sizes are actually in mm. a 185 shim is 1.85 mm

So when I measured with the new cam in place I found I needed to increase my shim size by .2 mm to get back to within specs which meant going from a 185 to a 205.

Thanks again for the help:thumbsup:

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