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Jackrat
6th October 2004, 20:15
Ok so I got a very good supplier of XS650s bits in the US.
Unlike the Ozy BS artist,this guy actualy delivers.
Anyway he has available hot street Cams for the XS.
Web grind#59a,,,,Valve lift .395,,,Duration 290, What ever that means.
Cost $175US plus I would need HP valve springs at $120US a set.
The blerb says it will incress the torque right across the Rev' range. :niceone:
Anybody else out there done something like this??was it worth the effort.
No, I will not just buy a different bike :msn-wink:

marty
6th October 2004, 20:42
duration is the degrees of cam rotation that the valve is moving for (i think).

it's gotta be the cheapest mod you can get for a bike, jack. what would it's idle be like though?

jrandom
6th October 2004, 20:48
what would it's idle be like though?

Shhh, don't mention that. This whole 'new cam' deal is actually just an excuse to start blipping the throttle while he waits at the lights, innit Jack? ;) :whistle:

Kickaha
6th October 2004, 20:49
Big Bore kit should do the same job,but may not be as cost effective as the cam and springs,perhaps you should do both :niceone:

Motu
6th October 2004, 20:49
Find out what the actual valve timing is...ie - inlet opens,inlet closes,like a B31 had io,25,ic 65,eo 65,ec 25 ....that's 270 deg duration,but the figures can move around a bit,most important...to me anyway.The Goldstar cam had 65,85...80,55,thats 330deg duration and 120deg overlap.The XS650 is close to a BSA A65,valve timing is too - I'd go for a Firebird Scrambler,or Spitfire grind.

Jackrat
6th October 2004, 21:28
Can't find any info on the standard valve timing in my magic book(not so magic at all).
I tried to get a big bore kit from OZ but the supplier failed to live up to his claims(that's being polite)
This Cam plus another few things from the same people seem the easiest and most cost effective way to go.
The people I'm dealing with are right up on the XS so I'm assuming they've chosen the best Cam for every day use and it won't be to crazy to live with.
As far as idling ect goes,,,See JRs comment. :shifty:

Motu
7th October 2004, 08:41
XS650 cam timing - inlet opens - 36deg BTDC
inlet closes - 68deg ABDC
exhaust opens - 68deg BBDC
exhaust closes - 36deg ATDC

Thats 284 deg duration and 72 deg overlap.

The XS1 and 2 and TX650 - inlet opens - 47deg BTDC
inlet closes - 67deg ABDC
exhaust opens - 60deg BBDC
exhaust closes - 41 deg ATDC

294 inlet duration...283 exhaust duration and 88 deg overlap.

The earlier motors are reputed to be more powerful,this is one reason why.The early cam is more BSA,the later more Bonnie.

Playing around with cams is fun,I used to swap cams,carbs and exhausts all over the place....good stuff.Sometimes it seems to make no difference and you wonder why the hell you did it,other times it makes a hell of a difference...and you wonder why in the hell you did it.Look for it being a little happier at higher revs.

Kickaha
17th October 2004, 08:20
I was looking for something else when I stumbled across this but it's a good write up on modifying a XS650

http://www.biker.co.nz/Reviews.asp?id=148