Who among us is interested in the above? Seems a lot of us have been timing our own cams & I wanted to gauge demand. Anyone willing to drill sprockets & at what cost? Yes, I know it's not too difficult but I'd rather pay & save myself the trouble. So, who has a need?
Drilled Cam Sprockets
- Thread starter IAG
- Start date
I would guess its quite low demand. A few years ago a bunch of us came up with different designs, vernier based, slot based, whatever. Cam, Keith, Phil, Red, me, and others. I don't remember a surge of enquiries for duplicates or designs.
Personally I just found it satisfying to get the factory timing bang on and then develop it from there. To be honest, I can't remember where I ended up, but I enjoyed messing around.
Personally I just found it satisfying to get the factory timing bang on and then develop it from there. To be honest, I can't remember where I ended up, but I enjoyed messing around.
paulincayman
Hero member
- Location
- Cayman Islands
I'm going from A11 to Axtell but also have a set of 4C ...How about a wheel with three sets of holes to service all options.
I'd be up for that..
I'd be up for that..
piranha-bro2
Hero member
- Location
- Melbourne
Getting them factory spot-on is one thing, but with some knowledge you can play with mods in cam timing to good effect - and the twin-cam motor offers much great er flexibility in this regard than the single cam twins. Of course, you really have to know your stuff and be very thorough, as issues such as overlap, valve contact with piston crowns and each other etc can be very destructive and costly.
CLEMTOG
Hero member
I am going to be doing some of this cam indexing thing fairly soon, with the help of someone who knows worlds and worlds more than me, and that will be a jota spec 1200 motor.
Later I will be doing the same with another engine and 7C cams, but the wheels on those do not have any factory marks at all, has anyone come across that before?
CLEM
Later I will be doing the same with another engine and 7C cams, but the wheels on those do not have any factory marks at all, has anyone come across that before?
CLEM
Piranha Brother 2 said:
Quentin,
We did a lot of experimenting regarding valve timing at Moto Witt, and usually reverted to stock settings... seldom a gain without a loss elsewhere.
Rarely found triple cams and markings far off from where they should be, at least not with factory parts. Very different on the twins though.
Want different timing, make new cams.
piet
phil37
Hero member
- Location
- Lincolnshire
doesn't really matter if you're going to degree it in properly Clem - Regards - Phil
CLEMTOG
Hero member
I suppose you are right Phil, but I thought maybe as a starting point?, but why would a set of wheels exist without marks?, just wondering,
I remember Gerry Adams (now deceased ex grass track Laverda sidecars) and Chris Atkinson, same, also Lav gras track sidecars, telling me that performance gains are to be had with only mild loss of low end if both cams are retarded by 4 degrees, but then, thinking about it both those motors were run on dope.
CLEM
CLEM
I remember Gerry Adams (now deceased ex grass track Laverda sidecars) and Chris Atkinson, same, also Lav gras track sidecars, telling me that performance gains are to be had with only mild loss of low end if both cams are retarded by 4 degrees, but then, thinking about it both those motors were run on dope.
CLEM
CLEM
piranha-bro2
Hero member
- Location
- Melbourne
CLEMTOG said:
I've run my SFC 5/C cams from 4-6 deg advanced (both in and ex lobes simultaneously obviously on a twin) for an increase in midrange. Without a dyno run I have no way of knowing whether it was successful or not. Certainly felt nice to ride, but a whole range of other mods will have contributed to that.
Piet, your post about lots of work done at OTC is interesting - triple owners take note! As for SF cams having in and ex permanently siamesed, I can visualise a mod where the in and ex cams from each side are split and some form of bolt-togetherness is incorporated. Couldn't be that hard compared to making a four-valve head! But for any possible supposed gain it's not worth it - and as you say, that's why we make new cams!
Phil Todd's reprofiled rockers for a 6/C cam probably operate similarly to altered cam timing, but with subtle differences - such as altering both opening AND closing independently, unlike advancing or retarding, which has the same effect on both opening and closing (ie later or earlier).