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ssian

Cylinder head for a 1983 XL600r the same as a 1986 xl600r

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Does any one know if a cylinder head off a 1983 Honda XL600r will fit a 1986?

The 1983 has some kind of reed valve for the oil, and the 86 does not.

ian

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Does any one know if a cylinder head off a 1983 Honda XL600r will fit a 1986?

The 1983 has some kind of reed valve for the oil, and the 86 does not.

ian

What are you talking about? I was just looking at the micro fische at honda see no real difference in the 83-87 heads. I have a 84 XL600R with the head removed right now, so if you could show a pic of what you are talking about maybe we could be of assistance.

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Yes there is a reed valve that lets a bit of air/fuel into the secondary intake port from the primary carb.

They only did this for 1983 and decided to ditch that idea.

There is no problem running a 1983 head on a 1984 to 1987 clinder/engine.

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Does anyone know where to get a new cam for an XL600? I ordered one for my 83' from Thumpertalk Store and they told me Honda didn't have any. Should I just try another year w/different part #, or is there some place to get a hotcam instead? When I checked hotcam's page they didn't list a cam for the dual carb head.

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The thought behind the reed valve on the XL600R was to let a little fuel get over to the right intake valve to keep it lubricated while the engine was operating only on the primary carb since the two carbs and intake tracts are completely seperated.

Turned out that most people like to feel the power of the second carb coming on, so the valve wasn't needed:thumbsup:

FYI the XL500 in certain years had an actual reed valve cage in the intake tract, just like a 2stroke. That was weired. The little reed in the XL600R isn't directly in the intake tract or blocking it in any way, there is a small cross-over between the intake ports that the reed valve controls which is suposed to allow flow into the secondary port and not from the secondary port into the primary.

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Ebay for $75 right now.

I emailed that ebay guy to find out the the years that cam fit. He said ALL. Clearly he has no clue there is a difference. I suspect they are for single carb heads only. The reed valve can be thrown away and the port pugged or left open. There's a crossover passage in the manifold that performs the same function. XL heads have larger intake ports than XRs. The insulator on XRs has a taper to match manifold to head while the XL insulator is straight thru bores. Personally I've only seen 83 XR500s having the reed and not XLs. Seems there are variations from US/Canada/Euro etc.

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I don't know about NOS(new old stock) cams for '83-87 twin carb engines, but aftermarket cams are limited to new billets(big $$$) or welded and reground OEM. Hot Cams does not offer anything for '83-87 RFVCs and the '88+ cam is not compatible.

Makes me really tempted to build a cam duplicator...

To answer the original question from 2006, yes, the cylinder head from a 1983 XL600 will work just fine on a 1986. You don't even have to do anything with the reed bypass valve.

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