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Cams for big bore kit

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I know a lot has been posted about big bore kits, and I've read quite a few threads, but have yet to find an answer for my question. If running a 270 or 290 kit in an older (mine is an '07) WR250F, is it necessary to change cams? And if so, what would you recommend for western trail riding? I'm a 185 pound vet intermediate ex-racer, and still like to zip along the trails and climb hills.

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I Only got experience of a 290 kit on a 03 wr  it worked great with just the 290 kit, got way stronger down low. Peak power probably is the same just at a lower rpm. Unless you like to rev your engine hard or really need more top end power there is no need for a cam change imo.

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Mostly agree with Rob. I did notice my top compromised tho, so if I were to put some cams in it would be to add some of those highs back.

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I've seen a few posts about running Hot Cams, with many recommendations for Stage 1 intake and Stage 2 exhaust. But most of this seems to be from guys who are tricking out YZ's . Would this cam combo work well for a WR for trail riding, or is this more of a race set up?

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50 minutes ago, rwphoto said:

I've seen a few posts about running Hot Cams, with many recommendations for Stage 1 intake and Stage 2 exhaust. But most of this seems to be from guys who are tricking out YZ's . Would this cam combo work well for a WR for trail riding, or is this more of a race set up?

Don't know about that setup. I would try just the big bore kit first. If your not happy just buy the cams later. Cams are what? $200 a piece? Ant it won't give you that much more power. 

 

Read this thread for a wr250f big bore build and dyno! : https://thumpertalk.com/forums/topic/696659-08-wr250f-from-stock-to-modified-process-and-dynos/

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I would call Web Camshafts and get their opinion. They offer wide range of cams and customs as well.

 

Generally speaking, the larger the displacement gets, the milder the cams act. A cam set that produces strong linear power as a 250 may sign off abruptly on top in a bigbore.

 

Hotcams produces cams for stock bikes per their own words to me. They used to make a set of cams that worked really well on LT-Z/DR-Z modified bigbores but discontinued them to make little bump sticks for choked up stock bikes.

I could be wrong up but my guess is even Hotcam's Stage 2's will go flat after the mid range in a bigbore.

 

 

 

 

 

 

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