Valk Rear Tire - Info

[sawdustar]

Let's see if I can do this.....Here is a table I put together to help me see via numbers and calculations to better understand what tire size differences mean to me in how many tire revolutions per mile I would get based on the different tire sizes.
The first line in the table is the stock Valkyrie Rear Tire Size. This is what I based all my other numbers on to compare against the factory stock size.

Based on the numbers, a 205/60-16 would be really close to the original stock tire performance based on Revolutions Per Mile numbers, where a 205/65-16 would help save you some engine RPMs by reducing the tire revolutions per mile by about 17 revolutions.

I don't know....maybe I'm just "splitting hairs" here....but I wanted to show/see this for myself and share this with the forum members for a reference only. I am no math whiz....just used Excel spreadsheet to work through this. I take no liability for any fault in the numbers.

Tire Size	SideWall	Diameter	Circumference	RevolutionsPerMile
180/70-16	4.960629921	25.92125984	81.43403949	778.0530156
195/60-16	4.606299213	25.21259843	79.20771399	799.9220885
205/50-16	4.035433071	24.07086614	75.62085624	837.8640914
205/55-16	4.438976378	24.87795276	78.15639361	810.6822369
205/60-16	4.842519685	25.68503937	80.69193099	785.2086227
205/65-16	5.246062992	26.49212598	83.22746837	761.2871236

[old2soon]

As REAL wurld as it gets. My first D/S was a 205-60-16. Little taller than stock. My next 2 D/S choices have both been 205-65-16. A little taller than stock and the 60 series. Each increase in tire height has caused a bit more lean to the side stand. When my Dragon is in her cave there is a 2X4 under her kickstand where it meets the concrete. I'm also on stock 13" long shocks. I can flat foot it at a stop. I do however pick my parking spaces with care. Lean of the parking lot-loose gravel/sand/trash etc etc. At I-12 in Eureka Springs Ar. a lot of us needed "stuff" under our kickstands as the top parking lot was wavy for lack of a better description.  I-13 at Lacrosse Wi. on the other hand had a fairly level biker friendly parking lot.  First time you need help pushing yer Phatt Ghurl backwards cause you DID NOT pay attention to the angle and surface of said lot you WILL understand WHY we call them PHATT GHURLS.  And good luck on yer tire choice. RIDE SAFE.

[John Schmidt]

It's pouring outside and I have nothing better to do, so here's my take on this. I have some "Conversion" software which will, among many other functions, convert inches to millmeters...or vice versa. After all was recomputed, here's my earth shaking results.  

180/70-16=25.92123" dia. X 3.14=81.3926622" circumference.
205/60-16=25.68501" dia. X 3.14=80.6509314" circumference.
5280' X 12"= 63,360" per mile.
So: 180/70-16 revolutions/mile=63,360/81.3926622=778.448551594
      205/60-16 revolutions/mile=63,360/80.6509314=785.607790265

Creating a differenc of 7.159238671 revolutions per mile between the 180/70 and the 205/60. Whew!!! Sure hope it stops raining soon.    

[R J]

I'd just say pick the size ya want and go for it.

I've pretty close to of had all those sizes under MGM in his day as 2 wheels.

Want me to be honest, outside of the side stand lean I couldn't really tell a difference in sizes.

PS:   I'm a short little fat crap, with 28" inseams.

I never had an trouble holding the old boy up at stop signs.

My choice was Good Year Triple Tread, and some of the members JUST FIRKIN hate that tire.   Those that I have run, no problem on any of mine.   I run them at 28#'s.    Started at 36#'s and kept coming down till I liked it and that is where I staid.     Lot of Iowa  riders on these tires like to run 32#'s.

[Jess from VA]

My GATTs are at 40 psi constant, and no irregular wear.

To each their own.

[salty1]

Thanks Sawduster for the effort, it's interesting to see actual numbers.

[Wewaman]

General Altimax 205/60 at 40psi
First I gotta say What is all this talk about getting used to a car tire  in reality you have to get used to a M/C tire.
This thing is just so Sweet to ride on I have SO much more confidence with this under me than I ever had with a M/C tire.
I've been told to run 32-36 psi and I might one day but right now 40 just rocks.  First ride was about 70 miles in the rain.
Then about 100 miles today in the sunshine she handles superb at low speed at least to me and also at high speeds /triple digits.  Very stable.

Those are just my opinion' s,
   Wewa

[Jess from VA]

W-man, I've been running 40 in my Goodyears for a long time.  I read of high center tread wear with higher inflation, so kept an eye on it, and it wore evenly all the way across to 37K.  If I try 30psi, it wallows so bad in corners it scares me.  I am sure different CTs act differently, but 40 is solid and responsive for me.  Also makes pushing the bike around and slow tight turns easier too.  Keep an eye on your tread wear, and do what makes you happy.

Welcome to the reckless endangerment (dark) side.   

[sawdustar]

Well, I didn't put this up here to get y'all to tell me the tire size I needed. It's with all the C/T and M/T talk over the last several days....I wanted to put numbers on the forum to show the mathematical difference between tire sizes. So I did. 

[Wewaman]

  got it thanks 
Wewa

[Rams]

Well, I didn't put this up here to get y'all to tell me the tire size I needed. It's with all the C/T and M/T talk over the last several days....I wanted to put numbers on the forum to show the mathematical difference between tire sizes. So I did. 

Good for you.   Before I went dark side, I went through a similar process using some different tire links to get the size I wanted.    I looked at a bunch of different tread patterns also.   I was not interested in going as wide as I could, I wanted to decrease the rpm at highway speeds.   I bought and installed an Austone Taxi Tire.    I read all the different opinions, listened to all the different warnings and made my decision.   I don't care what anyone else put on their bike, I'm very pleased with the decision I made.   The research paid off but, it helps knowing precisely the end result desired.   

[PhredValk]

To keep all the spec stuff on the same page...

Tire Speed Ratings:

L  75 mph  120 km/h   
M  81 mph  130 km/h   
N  87 mph  140 km/h   
P  93 mph  150 km/h   
Q  99 mph  160 km/h   
R  106 mph 170 km/h   
S  112 mph 180 km/h   
T  118 mph 190 km/h   
U  124 mph 200 km/h   
H  130 mph 210 km/h   
V  149 mph 240 km/h
Fred.

[xman]

Michelin Tire?
Michelin has a 180-65 -16  has anyone used it? The Michelin dual compound looks like a nice technology.  I guess it's 2% smaller in diameter. What do you guys think?

[R J]

Michelin is a very stiff sidewall tire.

I used to run them on my Cruiser as a CHP.   Loved em in the mtns.

As soon as I wear out the tires on my Dakota, I'll put Michelin's on it.

[Jim500]

Just to throw a wrench in the works... Not all tires of the same size are...the same size. Different tire manufacturers tires vary in width and height for the same given size. Just sayin....

[97BLKVALK]

Great Information.  Thanks for taking the time.

Michael

[Brian]

Awesome info here guys. I assume less revolutions per mile equals better gas mileage?