canadian needs head work

[bones150]

Where do us canadians go for a good head mod? How does S3 Head work or compare?

 

[Jakobi]

S3 offers about as much improvement as shaving the stock heads mating surface (and it looks good). The chamber volume is the same as stock, and the 3 inserts only change the depth/squish height to effectively reduce squish and increase compression, or bigger squish and less compression.

I'd recommend trying to source someone to mod your head properly for best results.

 

[robicon]

I cut down my cylinder to close the gap and increase my psi eric gorr did it with a replate. I am very happy with it. I have use riders edge in veron to build a set of wp forks and they are awesome. I have since found out that Ian does motor work and can do your head.

 

[bones150]

Yes I heard ian can shave my head, any machine shop could do that I guess. Seems like the most gain is in reshaping the dome.

 

[Jakobi]

Not neccessarily reshaping the dome. The squish band itself isn't too bad stock. The issue is if you have to shave too much to bring the squish band into effect, then you have also raised compression a significant amount. The more you need to shave the higher the CR. Take the CR too high and the bike will require high octane fuels. This is why most tuners will then remove some material from the chamber to correct the compression ratio.

I believe RB does some work to the squish band itself also.

 

[(F5)]

I think you'll find that to get the squish to work properly you will raise the compression above available fuel ratios so you need to get the com back to a usable figure.

Me I'm (when I get some more time) am going to skim it & reduce the com back to what it is now (Think mine currently measures at 12.7:1 full stroke, but I have it written down) so I can still kick it over easily, which is important to me but will still gain from better combustion, less lost squished gas.

Squish ratio area is probably about right for a dirtbike, so I intend to take from inside the dome, but if it is too difficult to get nice cuts with my hand ground lathe tools I'll steal from the squish area which is easy.