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Ever Roll Back The Throttle?

I would think that the modern bikes with cruise control should not need the throttle rolled on and off or using the cruise control would be bad for the bike
but as i live in an area where the roads are not straight in any plane i never go further than 1/4 mile without opening or closing the throttle there is always a bend or an incline up or down

Brian
 
Trek said:
Sounds like my kind of riding Brian. I love the twisties and hills.
Click to expand...

That is just the way the roads evolved here it is great on a motorcycle shortest way to get to the fast straight roads going south is 60 miles and down the east coast but i prefer to go straight through the highlands 150 miles to the fast straight roads distance to the same point in perth is about the same

Brian
 
Back in the 1960's it was common knowledge to roll off the throttle when running on a highway. You did this no matter what the brand. I was told that it formed a quick vacumn inside of the engine that would throw a mist of oil all over the insides of an engine. I never did find any technical stuff on proving this but it doesn't hurt any thing. Maybe it would suck back down some of the oil build up in the Shovel Heads. Harely did prove that one. An area rep told me that they were trying to get some idea where the oil was burnt in the Shovel because of looming EPA Regulations. They cut the tops off the rocker covers and glued on plexiglass. They ran an engine on a test stand at various speeds and couldn't find any thing. Then in frustration they just set the engine at highway speeds and let the engine run. In their amazement they saw the rockers fill totally up with oil. That forced oil down the valve guides. Thus the tighter valve guides in 1982 and thousands of stuck valves. In 1983 they tightened up the clearance and drilled holes in the bottom outside pushrod blocks and drilled a hole besides each one into the case. They were connected with a rubber hose and the oil burning was lessened a great deal but it was all for nothing as the EVO came on the scene in a couple of years.
 
When you let off throttle, engine vacuum goes high pulling oil up to rings. I don't know if oil will be pulled up top in rocker boxes.
wilks3
 
Used to have old school triumphs and the owners manual said to roll back on the throttle time to time for the same reason . Did it with my shovel and rodw it for 70k with out a rebuild. I still do it on my new bike too . I just don't do it when I'm riding in a group
 
In a 2 stroke it makes some sense, maybe. Unburnt fuel in the head with pre-mix in it... The only oiling of the top of the cylinder that I can think of in a 4 stroke might be from vacuum pulling it through the breathers. Hmmm interesting thread though
 
Frankly, I don't see too much point in "rolling back the throttle"...just ride it and be comfortable. Constant throttle on a new engine is not good for ring seating and because the engine is very "tight" could cause problems. That is why the break in procedure in the Self Help section. :newsmile01:

But for routine operation of your bike afterwards it probably won't do much of anything, as Fossil pointed out. I remember doing throttle chops when doing carb A/F mixture jetting by checking the plugs for color back in the days of leaded gas. But nowadays even that does not work as well...with performance and fuel mileage being more of a balancing act.:newsmile091:
 
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