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05 wr250f to yz cam timing?? (or hotcams!)

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Hi guys, sorry if this has been covered before. I was wondering if the 05 wr250f cam timing can be re-timed to a yz setting or are they the same for this year of WR. I've searched the FAQ but cound'nt find 05 info only to 04.

Also, which cam, inlet/exhaust would be more beneficial to upgrade to a hotcam??

By the way, great forum guys.

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Hi guys, sorry if this has been covered before. I was wondering if the 05 wr250f cam timing can be re-timed to a yz setting or are they the same for this year of WR. I've searched the FAQ but cound'nt find 05 info only to 04.

Also, which cam, inlet/exhaust would be more beneficial to upgrade to a hotcam??

By the way, great forum guys.

I am just about positive, you can't alter the exhaust cam timing on any WR starting from '03 and up. If you try to retard the cam timing to mimic the YZ's, it throws off the decompressor mechanism timing. If you want YZ timing, you have to buy the YZ exhaust cam.

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Thanks polar, I had a wr426 01 before, which I re-timed the cam's on. Made a heap of difference. I might check with the dealer. I'll leave a post on the outcome.

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With 03 models on to change the exhaust cam to YZ specs you need to grind 1mm of the auto decompresion lug. I have just put a Hotcam exhaust cam into my 04 WR and it made a huge diference. It gives the bike a huge boost in low to midrange power. Im running 14/52 gearing and it pulls it easily. Putting the Hotcam inlet in as well should give you more power right of the bottom. HotCams dont recomend running there inlet with the standard WR exhaust cam.

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I have an '05 WR250F and last week bought an '05 YZ250F auto decompression exhaust cam off of E-Bay. I also bought an '04 YZ250F silencer from a fellow TTer. I installed the silencer and had the local dealer install the cam and rejet my bike. It's a whole new machine, lots more power, much more fun and exciting. Now, I have one week to get used to it before the Starvation Ridge 25 hour race. Money well spent!!!

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I'v had a look on the hotcam website and the dyno charts for the inlet and exhaust cams. It looks like they produce the extra power in the low and mid range. Sounds just about right. I'll have to have a think about the $360 price tag for the set!

Thanks for the feedback guys

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Thanks redr1boy, I've had a quick brouse over the wr to yzf exhaust cam page, but theres no mention of 05 models only to 04. The exchange is straight forward as I've rebuilt these engines from the gearbox up. Just want to be sure the new cam fits without any issues before buying one.

Does changing the exhaust cam affect the decomprssor timing on the 05 models??

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Thanks redr1boy, I've had a quick brouse over the wr to yzf exhaust cam page, but theres no mention of 05 models only to 04. The exchange is straight forward as I've rebuilt these engines from the gearbox up. Just want to be sure the new cam fits without any issues before buying one.

Does changing the exhaust cam affect the decomprssor timing on the 05 models??

thumperfaq has not been updated in some time. These engines, however, also have not changed. So, the info still applies.

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I'v had a look on the hotcam website and the dyno charts for the inlet and exhaust cams. It looks like they produce the extra power in the low and mid range. Sounds just about right. I'll have to have a think about the $360 price tag for the set!

Thanks for the feedback guys

There is a guy on E-bay that has them for $258 (or something like that) for the set. Not sure if he ships to UK or not, though, says United States.

YZ250F Hotcams

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