Degreeing my cams

[Anonymous]

Does 106 go for all GS motors? My 400 hits the wall before red-line in 6th gear so I'd like to do this instead of changing drive sprockets. I should be able to get another 10km/h out of her which would be nice.

Steve

[KEITH KRAUSE]

Does 106 go for all GS motors? My 400 hits the wall before red-line in 6th gear so I'd like to do this instead of changing drive sprockets. I should be able to get another 10km/h out of her which would be nice.

Steve

This is what I've read. Combustion chamber configuration is important. The semi-hemispherical chambers of MOST older DOHC Japanese engines work well with a setting of 104-108 degrees.
If you are trying to increase the top end HP, you would want 108 degrees minimum and maybe 110. This will result in a narrower powerband and less low/mid-range power. On a small motor I would rather have the low/mid-range power the best it can be. Just my opinion.

[Anonymous]

Keith - while I believe your opinions on the effect of lobe centers on performance are valid, this topic started with Craig wanting to degree what I believe to be a set of Non-Factory cams, (though this has not yet been made completely clear). The manufacturers recommendations which I refer to are those of the cam manufacturer, not Suzuki. Somewhere on the face of this earth, somebody sat down and designed a non-stock cam with the profile he has selected. They ran it in an engine on a dyno and declared that "this is good, lets sell it". Before they came to this conclusion they spent many hours and dollars refining their camshaft to create good performance in a certain application. So my point is this: if this cam does not create the power band that Craig wants, he should probably look for different cams. Yes, minor shifts in the peak of the power band can be made by advancing or retarding the cam but, and I repeat myself, this cams ultimate total horsepower will be made in the "straight up" position designed by the manufacturer. The great value in degreeing the cams, as you have indicated, comes more from setting the cams accurately to the manufacturer's spec., than from shifting the power band up or down.

[RacingJake]

There is one point in this thread which seems to have been completely overlooked. That is; what is the manufacturers recommended installation center?

I'm going with G4 cams using the OEM sprockets and after a few runs down the track I'll install my adjustable sprockets at 110 degrees and see if there's a differance. Cam Motions recomends 110.

Jake

[Anonymous]

Jake - I like your thinking. Though much more labor intensive, your approach is the ultimate answer to questions such as this. Even a dyno sheet does not always give you a "perfect" answer as to how the bike will perform on the street or strip, (unless you already have a well established baseline of dyno and real world performance, which most of us don't).

[Craig]

Keith - while I believe your opinions on the effect of lobe centers on performance are valid, this topic started with Craig wanting to degree what I believe to be a set of Non-Factory cams, (though this has not yet been made completely clear). The manufacturers recommendations which I refer to are those of the cam manufacturer, not Suzuki. Somewhere on the face of this earth, somebody sat down and designed a non-stock cam with the profile he has selected. They ran it in an engine on a dyno and declared that "this is good, lets sell it". Before they came to this conclusion they spent many hours and dollars refining their camshaft to create good performance in a certain application. So my point is this: if this cam does not create the power band that Craig wants, he should probably look for different cams. Yes, minor shifts in the peak of the power band can be made by advancing or retarding the cam but, and I repeat myself, this cams ultimate total horsepower will be made in the "straight up" position designed by the manufacturer. The great value in degreeing the cams, as you have indicated, comes more from setting the cams accurately to the manufacturer's spec., than from shifting the power band up or down.

THe cams in question are "Web Cam" .348" lift , 257 degree Dur @ .050". They state that these cams are for "Hot street & strip big bore motors. Strong mid range and top end." I have not sopped there. I am also putting in a 1168 cc kit as I have 1.5 thou. tapper in my cylinders---time for a re-bore anyways. I believe that the crank is welded by the factory in these engines. THe head is to get a complete redo and I have not yet decided if I can aford to get it ported and polished. The ingition has been repladed with at Dyna 2000 which will give me some room to play with. I hope I have not gotten myself into a tuneing nightmare, however, I have access to a dyno which should help. I apprecieate all of the activity that my question has created. It is nice to have people with what appearts to be lots of experience in these bikes. If anyone makes it up to central Alberta, pleae let me know and I will show you some very nice roads!!