Sifton Cams are too big

[73ironhead]

Just got the $310 Sifton cam kit in from V-twin and they don't fit; just three of them have a hard time turning. Vtwin says they are good for 71-80; I have a '73. Any ideas..? thanks

[Wicked]

So you got 3 cams in. Which 3? Are the lifters in? Cam cover on? You check cam end play? What is hard to turn? Did you replace cam bearings and bushings?

[73ironhead]

engine is apart, no lifters, new bearings, no need to replace bushings, the kit is complete with four cams but when I try to place them in the cam cover the teeth are too tight and can't get them to turn..are PB+ bigger than P?

[nibroc]

call sifton--they might tell ya to go to minus-minus

[garyajaz]

mike cams and measure bushings.
if tight or very loose.  found it.
also if cams not supported by bearings may wobble tight.

[73ironhead]

found couple of old P cams with extra oil tracts on N2 larger gear and using those. I order them after I read Tom Sifton story of building cams that allowed you to keep the gas all open..wish I new about this 30 years ago...much obliged gents..

[garyajaz]

they were tight and larger gear made them loose?
I think I missing something here .

and cams allowing to keep gas open?

[JW113]

Try putting the cams in one at a time, see if they turn OK. If they don't, problem is probably with the bushings too tight. I seriously doubt this is the problem though. Mic the outer journals and compare to the stock cams that came out of it if you have a 1" micrometer.

If they spin fine, as I think they will, the gears are too tight, i.e. too big. Have a gander at this:

http://www.andrewsproducts.com/sites/www.andrewsproducts.com/files/catalog_pdfs/2014-page21.pdf

I am not familiar with the "new" Sifton gears, so no idea if they support the same way Andrews does.

-JW

[panic]

Lobe size has nothing to do with it.

Reasons:
1. pitch diameter is too large
2. cam bearing locations in the right case contain errors

Do they all fit in the cam cover?

[Racepres]

found couple of old P cams with extra oil tracts on N2 larger gear and using those. I order them after I read Tom Sifton story of building cams that allowed you to keep the gas all open..wish I new about this 30 years ago...much obliged gents..

De-code/translate for me please!!!