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Need a Cam for XR650L

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Have the top end opened up on Dad's 650L again - one exhaust rocker was too loose so I pulled the engine to have a look see and found a little pitting and wear on one lobe and rocker.

Might as well get a new cam as the rest of the engine is good. Currently has a 101mm 10.5:1 JE piston and FCR carb - otherwise it is stock.

What cam should I go for? First priority is always low end/mid range power. Don't want to go wild, just a bump over stock while maintaining durability/reliability (I.E. not comfortable with Hotcams in this engine).

 

Any suggestions?

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A cam will give you top and mid power.......... your  10:5 piston shows more low end power than any cam can match,,,,,,,,,,,,,,,,,,,

BUT a stock is a good bottom end cam, believe it or not.

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On 12/11/2018 at 2:07 PM, EarthCruzn said:

A cam will give you top and mid power.......... your  10:5 piston shows more low end power than any cam can match,,,,,,,,,,,,,,,,,,,

BUT a stock is a good bottom end cam, believe it or not.

I do believe that the stock cam is good for the bottom end power - the smaller and more conservative the cam, the better it will be on the low end. I would like something that retains most of the bottom end with a good bump in the mid range.

Anyone know what the stock cam specs are?

I like the looks of Web Cam's smallest cam for the 650L with these specs:

Valve lift: .355/.355

Duration: 267°/267°

Duration @ .050: 242°/242°

At least in the automotive engine world, these specs are quite mild.

How would this cam compare to the stocker?

 

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25 minutes ago, 1972RedNeck said:

I do believe that the stock cam is good for the bottom end power - the smaller and more conservative the cam, the better it will be on the low end. I would like something that retains most of the bottom end with a good bump in the mid range.

Anyone know what the stock cam specs are?

I like the looks of Web Cam's smallest cam for the 650L with these specs:

Valve lift: .355/.355

Duration: 267°/267°

Duration @ .050: 242°/242°

At least in the automotive engine world, these specs are quite mild.

How would this cam compare to the stocker?

 

I've never found anything on the stock cam specs.  I asked Web Cam but the girl only sent me their cam information.  She may have misunderstood what I wanted but I never asked again to try to get the stock specs.  I'd think they would have to know them.

It does appear to be a mild cam but the lift on a 4 valve head cam won't be nearly what you're probably used to on a 2 valve head.

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11 hours ago, JoeRC51 said:

Don't forget you'll need your rockers hard welded with that cam.

Yup, if I were to go with them, I would have them do the rockers as well.

10 hours ago, Hollerhead said:

I've never found anything on the stock cam specs.  I asked Web Cam but the girl only sent me their cam information.  She may have misunderstood what I wanted but I never asked again to try to get the stock specs.  I'd think they would have to know them.

It does appear to be a mild cam but the lift on a 4 valve head cam won't be nearly what you're probably used to on a 2 valve head.

Agreed. I was looking at the duration - More duration = more top end in general.

 

So is that a good cam to run?

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I run the Web Cam 450/451 in my L.

It runs pretty good but it is expensive with the hardened rockers.

I'd make sure to put a Ignitech programmable CDI box on it.

The cdi box with the right curve in it makes a big difference.

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