Join Date: Dec 2015
Thanked 7 Times in 6 Posts
Low Topspeed, possible causes and solutions?
I am generally unable to break 80mph on my motorcycle unless slope or winds are in my favor (even then the gain is only 3-4mph). I tuck in as best I can, as getting above 73mph is very difficult for me otherwise.
I have looked over my previous posts and have reviewed many of the prior threads on top speed and I keep coming across people hitting 90-100mph without too much difficulty. The speed limit for I-10 and I-20 (which I do use on occasion and are the most practical options for travel in the area) is 80mph. Being able to just barely go the speed limit on a heavily used and vital route kills a lot of the enjoyment while riding.
I will freely admit that I am big, at 270lb and 6'1", but some of the posters have gotten speeds higher then mine with bikes nearly as weighted down or more so then mine.
I was new to riding when I got the bike. I never inquired if the previous owner did the 600mi service check and am still running the original chain and rear sprocket on the bike (~10000mi on odo). I've noted that even after cleaning and lubing the chain there are a number of tight spots and kinked areas.
So all that said here are my questions:
1) Would out of spec. valve clearance cause a lower then normal top speed? (Bonus question: how would the internals look after 10000mi of out of spec valve clearance?
2) How much power would a worn and/or stiff chain rob transferring power to the rear wheel?
3) Would there be any other causes for a lower then average top speed?
For the record, I use 86/87 octane gasoline, have changed out the airfilter already, change the oil every ~3000mi, and keep my tires at ~30psi. I typically average 50mpg-55mpg.
2013 Black CBR250R ABS, forced to haul my 6'1 270lb butt.
Last edited by TestBacon; 03-13-2017 at 04:48 AM.