speed difference

Status
Not open for further replies.

bob58o

SuckSqueezeBangBlow
Messages
9,646
Reaction score
1,840
Location
Chicago-town USA
18" Tires. Clutch. 95 :12 (7.9 :1) sprocket ratio...
That's around 7200 RPM for 48.8 mph.

18" Tires. 30 Series TC with 6" Driven Unit. 95:12 sprocket ratio. 7.125 :1 Final Drive Ratio...
That's around 6000 RPM for 45 mph.

With stock springs, I'd be interested to know how the valves aren't floating before 7200 RPM as well. Most people around here say they float em before 6k, but I know people that race with "stock" 10.8 lb springs get 6k and above. Some have said above 7100 on a Box Stock Clone.

I've never floated the valves on my stuff (AFAIK). I've always upgraded springs and connecting rods.

https://karting.4cycle.com/showthread.php?6829-max-rpm-and-temp
 

tgus3

a member
Messages
241
Reaction score
3
Location
a long ways from the end of the rainbow
Thats link doesnt work for me..like i said my engines almost completely stock except for exhaust and governor.Are you saying thats theres something different about it?...
How high is it probly revving without the gov?
 
Last edited:

bob58o

SuckSqueezeBangBlow
Messages
9,646
Reaction score
1,840
Location
Chicago-town USA
Thats link doesnt work for me..like i said my engines almost completely stock except for exhaust and governor.Are you saying thats theres something different about it?...
How high is it probly revving without the gov?

I guess I'm saying that the tire size (18") and sprockets used (95: 12) means you would have to be turning more RPMs to go 44 mph with a clutch than most people get out of the stock cam and springs. With the clutch on flat ground going 44mph, you are looking at 6500 RPM.

Going 45mph with the 30 series TC is about 6000 RPM.

Many here claim valve float around 5200-5400 RPM. I personally have never pushed a stock engine that high. I guess I'm saying your engine revs higher than others have claimed the stock springs allow.

Staying at WOT for long times (especially down hill) might cause valve float. With the stock retainers, I might be afraid of dropping a valve.
 
Status
Not open for further replies.
Top