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Dynoguy

XR Head work, dyno project.

12 posts in this topic

Hey,

It's been a long time since I posted here.

I'm looking to Dyno a stock XR650 and chart the changes of different parts. Specifically I'm looking for bikes that have had head porting work done.

So if anyone is planning on porting their head and installing a cam, from a stock engine to hopped up.. I'd like to dyno it and get snap shots of the differences as parts are installed. I have an XR600R 100mm bore, that has the head done by XR's only with big fins and all.. and it's faster than all get out.. but I bought it like this so I didn't get to see the difference's as it was built up.

I'm in the bay area and have a dyno at my house.

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bay area? in AZ?

How funny!! As I was asking my wife where in the world is the Bay area located in Arizona I look down and see Martinfan's same question LOL! I think there's a country song about ocean front property in AZ isnt there?

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Actually don't go nuts with the porting i'm told.

I had mine matchported and cleaned up,but they reckon the stock head is damn goodses.

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Yes, I agree with wesKC35K, the heads tend to flow well as std and its apparently all too easy to make them worse if you remove metal from the wrong areas.

Bigger valves might help give more power on the 600r etc but then it would'nt be long till the head starts to crack btwn the valve seats and spark plug holes.

Its handy experimenting on a flow rig first!

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ya there is LOL!

where in NV are ya? im in CARSON CITY.

Las Vegas. Theres some great riding around here believe it or not. Sorry to hijack from the topic!

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Actually don't go nuts with the porting i'm told.

I had mine matchported and cleaned up,but they reckon the stock head is damn goodses.

Mine was ported by Xr's only and it makes allot of power. As soon as I fix the suspension, I blew out the rear shock, I'll post some #'s and what's been done. It's around 50hp..

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With a 100 bore, porting, cam, decent carb and exh it should be making around 48-50HP Id estimate

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With a 100 bore, porting, cam, decent carb and exh it should be making around 48-50HP Id estimate

with hi compression.

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