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Did you verify cam timing??
50 RWHP is less than a stock 750? My 836 with a stock un-ported K1 head and Weber carbs with 30mm chokes put out 70 RWHP on the dyno, and I believe with a ported head would be close to 80. Can you post the dyno printout?
My 836 with ported head, 34mm in valves same cam and carbs as you gave 80rwhp.Jets: Main 135 (150), pilot 30 (27.5), needles 4:th (as std), fuel screws 1.5 turns out. KN pod filters and rather open 4-1. main 150 might be for vel stacksChanged main to 130 with 4-4 without diffusers. This is too lean.Ignition might be retarded which make engine powerless. I heard pinging from low so I retarded ignition and lost the pinging AND power. Too lean carbs got richer mixture (pilot) and correct ignition woke up the power.
I'm running 137.5-142 mains, RS34's, 1080 kit, hi compression, 327 cam ,ported head, etc, @ least 110hp. You are too rich my .02, but you gotta check all the other things mentioned, G'luck, Bill
"leak down" ? I have done a compressiontest a it was between 9 and 10
Thanks Mike the tool i used for messuring is not a precise tool, just giving me a compression reading on each cylinder. I can see this leak down tool is very helpful.I'm almost sure now, my timing is not correct, almost 10 degree off on a quick messure. Have to work on that Sent from my iPhone using Tapatalk
Where are you measuring the 10 degree error, at the cam? There are 34 teeth on the cam sprocket, so 10.588 degrees per tooth.Does your compression tester read in Bar? One Bar equals about 14.5 PSI, so 10 Bar is 145 PSI. Cam timing will also affect cranking compression, so verify that first.
Quote from: SunLar on October 08, 2016, 03:47:41 pmThanks Mike the tool i used for messuring is not a precise tool, just giving me a compression reading on each cylinder. I can see this leak down tool is very helpful.I'm almost sure now, my timing is not correct, almost 10 degree off on a quick messure. Have to work on that Sent from my iPhone using Tapatalk Yes....bad cam timing will have a very bad effect on performance. I know through past experience. We all need experience to become better.
I runned old RC 836 that have a dome that fits the head with widened chamber. Old style to open chambers and have pistons with wider domes.- Cam timing correct? I timed my SS-1 cam IN: 22/55, EX: 56/24 @ 1mm lift and 0 lift (measured total lift was 9.18mm IN and EX). I tightened the valve adjuster screw until the valve started to lift (needle moved 0.01-0.02 mm) to remove all play.- Really too rich with higher throttle lift?- You have pods?- Do you have an A/F measurement when running the Dyno? My dyno chart has it when a sensor was sticked into the exhaust. Measured at WOT.I had 132.5 main when that dyno was done. I changed cam to RC295 copy and 135 gave more torque when twisting throttle on 5:th gear from 80-90km/h.I reduced the acc pump stroke later on, to min setting. I checked the floats before and reduced carb 1-2. I saw this summer that cyl 1-2 ran extra lean close to damage and $$$$.I have purchased 3 more clear tube tube tools (VM29 tools) so I can check all 4 at the same time. Wego III Air/fuel sensor kit is under shipping, here next week. I'll check all cylinders one by one next year. Sensor in a sniffer pipe to be mounted into the exhaust. Measure during normal driving, not only WOT. It will cost a lot if it runs too lean at 100-120km/h and pistons will melt. The throttles are not much opened at that range.I secured the carbs in frame when it's not good have them hanging and bouncing up-down in carb boots only. Thick strap and rubber hose against frame secure the rack
Quote from: PeWe on October 08, 2016, 01:52:39 amI runned old RC 836 that have a dome that fits the head with widened chamber. Old style to open chambers and have pistons with wider domes.- Cam timing correct? I timed my SS-1 cam IN: 22/55, EX: 56/24 @ 1mm lift and 0 lift (measured total lift was 9.18mm IN and EX). I tightened the valve adjuster screw until the valve started to lift (needle moved 0.01-0.02 mm) to remove all play.- Really too rich with higher throttle lift?- You have pods?- Do you have an A/F measurement when running the Dyno? My dyno chart has it when a sensor was sticked into the exhaust. Measured at WOT.I had 132.5 main when that dyno was done. I changed cam to RC295 copy and 135 gave more torque when twisting throttle on 5:th gear from 80-90km/h.I reduced the acc pump stroke later on, to min setting. I checked the floats before and reduced carb 1-2. I saw this summer that cyl 1-2 ran extra lean close to damage and $$$$.I have purchased 3 more clear tube tube tools (VM29 tools) so I can check all 4 at the same time. Wego III Air/fuel sensor kit is under shipping, here next week. I'll check all cylinders one by one next year. Sensor in a sniffer pipe to be mounted into the exhaust. Measure during normal driving, not only WOT. It will cost a lot if it runs too lean at 100-120km/h and pistons will melt. The throttles are not much opened at that range.I secured the carbs in frame when it's not good have them hanging and bouncing up-down in carb boots only. Thick strap and rubber hose against frame secure the rackIs your cam timing according to Action Fours specification chart that you previous sent to me?
