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1,995 Posts
I have had the chance to spend a little time with the bike now, and also was able to get it back on the dyno today. Suprisingly the A/F really wasnt that far off...even with the accel pumps enabled.
For comparison the 1st sheet is the bike prior to having the exhaust cam advanced 1 tooth, and with the stock cvk carbs.
75.36 hp
59.93 lbft of torque
The sheet below is from today, this is the same dyno as the sheet above.
82.30 hp
61.06 lbft of torque
The carbs still need some work regarding tune...the bike is lean at idle...and rich around cruising speeds of 65/70 mph. We dropped the main's from 145's to 142.5 to bring the bike closer to 13 at cruising. I have the needles setup on notch #5...they are raised all the way up. I backed out of doing anymore tuning on the dyno and bought another pair of needles. After I get those in I'll get the bike back to the shop for another run...and maybe swap out the pilot's.
While the peak torque is nearly the same, the curve is much flatter....the bike pull's great and is a thrill to ride.
Comparing these carb's to the stock cvk's is difficult regarding drivability...rather like comparing say...a Sport bike to a Harley. Two totally different piece's of equipment...I don't believe...( I may be wrong )...that either the mikuni's or the fcr's will ever hold the level of drivability of the cvk's. These carbs..( mikuni's/fcr's )...simply are not constant velocity carbs.
The power come's on rather abruptly, not to the point where it's undriveable by any means...I do find myself now having to be much more self aware of how smooth I am with the throttle however. Learning smooth throttle control is a good thing.
I'd recommend these carbs to anyone serious about building hp.
No telling at this point whether or not advancing the exhaust
cam made any difference on paper...as I had said before...I doubt it made any real difference on paper. The real benefit however is by the seat of the pant's feel of the bike.
For comparison the 1st sheet is the bike prior to having the exhaust cam advanced 1 tooth, and with the stock cvk carbs.

75.36 hp
59.93 lbft of torque
The sheet below is from today, this is the same dyno as the sheet above.

82.30 hp
61.06 lbft of torque
The carbs still need some work regarding tune...the bike is lean at idle...and rich around cruising speeds of 65/70 mph. We dropped the main's from 145's to 142.5 to bring the bike closer to 13 at cruising. I have the needles setup on notch #5...they are raised all the way up. I backed out of doing anymore tuning on the dyno and bought another pair of needles. After I get those in I'll get the bike back to the shop for another run...and maybe swap out the pilot's.
While the peak torque is nearly the same, the curve is much flatter....the bike pull's great and is a thrill to ride.
Comparing these carb's to the stock cvk's is difficult regarding drivability...rather like comparing say...a Sport bike to a Harley. Two totally different piece's of equipment...I don't believe...( I may be wrong )...that either the mikuni's or the fcr's will ever hold the level of drivability of the cvk's. These carbs..( mikuni's/fcr's )...simply are not constant velocity carbs.
The power come's on rather abruptly, not to the point where it's undriveable by any means...I do find myself now having to be much more self aware of how smooth I am with the throttle however. Learning smooth throttle control is a good thing.
I'd recommend these carbs to anyone serious about building hp.
No telling at this point whether or not advancing the exhaust
cam made any difference on paper...as I had said before...I doubt it made any real difference on paper. The real benefit however is by the seat of the pant's feel of the bike.