-
Enjoy XS650.com? Consider making a donation to help support the site.
XS650.com receives a small share of sales from some links on this page, but direct donations have a much greater impact on keeping this site going.
Shell cam and MIKEs XS BB kit project
- Thread starter wolds
- Start date
racerdave
^ Gone not forgotten ^
Wow. Nice paint.
yamageddon
XS650 Addict
That bodywork looks great on the bike!
WOW - THAT is a beautiful bike Wolds!
I must say, between you and OHRider's snazzy orange machine, I am re-thinking the colour scheme on my own Special-to-Cafe bike....
I must say, between you and OHRider's snazzy orange machine, I am re-thinking the colour scheme on my own Special-to-Cafe bike....
bikefreak69
XS650 Enthusiast
Nice scooter!
wolds
XS650 Enthusiast
Congratulations Wolds, that's a fantastic idea/build/transformation of our beloved XS650. I love the end result and I will hereby nominate your bike for the 2019 Calendar (is it too early?) Enjoy.......
Yes. Be sure to get some high-res pics. Before the Winter scramble...
It looked good black, it looks even better now. Enjoy it.
yamageddon
XS650 Addict
Awesome!
mcjongs
XS650 Member
Nice bike!
XS650 is kind of new to me despite it was my first ''large'' motorcycle I bought back in 1986 when I was 23 years old..
I'm just now about to put together a 750cc Heiden tuning kit with the Shell #1 cam bought from Gary Hoos but I have a question re. the need for a base gasket? I plan to grind away some of the valve pocket edges protruding outwards in the combustion chamber and hence I'd like to compensate CR a little with not using the base gasket. This might be just be of minor effect but I would like to know if deck height/piston to head clearance of 1mm is OK or to little?
What about valve seats angles and grinding.. Anyone have knowledge of optimizing the seat angles etc.?
Regards Jon
XS650 is kind of new to me despite it was my first ''large'' motorcycle I bought back in 1986 when I was 23 years old..
I'm just now about to put together a 750cc Heiden tuning kit with the Shell #1 cam bought from Gary Hoos but I have a question re. the need for a base gasket? I plan to grind away some of the valve pocket edges protruding outwards in the combustion chamber and hence I'd like to compensate CR a little with not using the base gasket. This might be just be of minor effect but I would like to know if deck height/piston to head clearance of 1mm is OK or to little?
What about valve seats angles and grinding.. Anyone have knowledge of optimizing the seat angles etc.?
Regards Jon
It is not unheard of to run without a base gasket.
Here are my initial thoughts.
I would not be rushing in to modify the head, but you may have the knowledge and skill to be able to do this without detrimental effects on the engines performance.
From memory the 750cc Heiden kit is advertised as 10:1 CR which is pretty much the limit for a useable road bike. A small reduction in CR will probably make the bike easier to live with
Running without a base gasket will also alter your cam timing so you will probably need to press the sprocket off and reset it unless you have an adjustable cam sprocket.
Measure the CR and clearances before you alter anything with and without the base gasket then you will know the difference the gasket makes.
These bikes are getting old and in the past the head may have been skimmed to restore flatness.
As well as squish there is also valve to valve and piston to valve clearances to confirm.
The XS 650/750 Engine Modification Guide available from 650 Central as a download has all the info you require regarding clearances. Its good value for money
http://650central.com/
Here are my initial thoughts.
I would not be rushing in to modify the head, but you may have the knowledge and skill to be able to do this without detrimental effects on the engines performance.
From memory the 750cc Heiden kit is advertised as 10:1 CR which is pretty much the limit for a useable road bike. A small reduction in CR will probably make the bike easier to live with
Running without a base gasket will also alter your cam timing so you will probably need to press the sprocket off and reset it unless you have an adjustable cam sprocket.
Measure the CR and clearances before you alter anything with and without the base gasket then you will know the difference the gasket makes.
These bikes are getting old and in the past the head may have been skimmed to restore flatness.
As well as squish there is also valve to valve and piston to valve clearances to confirm.
The XS 650/750 Engine Modification Guide available from 650 Central as a download has all the info you require regarding clearances. Its good value for money
http://650central.com/
mcjongs
XS650 Member
The CR is 9,4:1 on this kit.
So maybe it will be reduced to 9,2.. so not that big deal maybe. Re. deck height..I'm confident with 1,4 mm in deck heigh on tuned Beetle flat 4 engines but everything is more heavy and crank is flexing more as well so hope that 1mm is enough.
Jon
So maybe it will be reduced to 9,2.. so not that big deal maybe. Re. deck height..I'm confident with 1,4 mm in deck heigh on tuned Beetle flat 4 engines but everything is more heavy and crank is flexing more as well so hope that 1mm is enough.
Jon
mcjongs
XS650 Member
I regret I obeyed the base gasket.. I think the light grinding of the valve pockets only reduce the CR with 0,1 or so.. Anyway, finished the head today. Because the head was in a very good shape, only light valve cleaning and seat refreshment with my valve grinder kit and light lapping in was necessary .. I was also glad that I could go with my friend to his works workshop today and glass blast the head. He also had a small diameter rotating file smaller that mine so I could clean up closer to the valve guides. In fact I had two heads and the one that is dirty was the one on the motor originally but I must say it was very rough and had poor alignment between the aluminum and the steel insert/combustion chamber where it mates with the inlet as well as the exhaust ports.. Now I'm only waiting for new valve seals.
Attachments
Last edited:
I just realized Wolds' bike missed going in the 2019 calendar.
It should be nominated for 2020!
It should be nominated for 2020!
Wow simply beautiful!!! Great build and for sure would be a great pic for calendar bike!
Nice bike! Just out of curiosity what did you end up running for the exhaust valve clearence?
wolds
XS650 Enthusiast
I'm running 0.006" for the intake and 0.008" for the exhaust
With my Shell#1 I have my lash at .006” intake and .009” exhaust and it has been running quiet no issues. One day if I’m bored I may try to go 0.010” on the exhaust, but when I had .011” it was ticking.
wolds
XS650 Enthusiast
More seat time for the exhaust (in particular) isn't a bad thing as it helps cool the valve. Anyone have thoughts on how the delay in closing changes performance?
Similar threads
- Price: $1500
- Minden, NV
