CBR250R Vetter style aero mods

[3-Wheeler]

Originally Posted by sendler

.... Cross winds are a complete non issue with this little tail.


.

Scott,

It's nice to hear that side-winds are a minor factor for your new tail. Nice work!!

Looks like you can get "four bags of groceries" in there!

Jim.

[sendler]

Originally Posted by 3-Wheeler

Looks like you can get "four bags of groceries" in there!

Jim.

We shall see if it does fit. I could easily carry the equivalent volume in the regular bags that I use but he likes to see the big, reusable bags that he uses sitting upright as if you were placing them in the trunk of a car.

[sendler]

9 tanks runthrough with the tail on my Honda CBR250R are as follows:
66 7/28/15 244.60 2.307 106.02 mpgUS
65 7/22/15 240.40 2.354 102.12
64 7/9/15 240.50 2.345 102.56
63 7/6/15 165.90 1.647 100.73
62 7/2/15 241.50 2.482 97.30
61 6/26/15 245.80 2.394 102.67
60 6/19/15 241.80 2.482 97.42
59 6/16/15 244.00 2.545 95.87
58 6/12/15 246.80 2.575 95.84

[3-Wheeler]

Originally Posted by sendler

9 tanks runthrough with the tail on my Honda CBR250R are as follows:
66 7/28/15 244.60 2.307 106.02 mpgUS
65 7/22/15 240.40 2.354 102.12
64 7/9/15 240.50 2.345 102.56
63 7/6/15 165.90 1.647 100.73
62 7/2/15 241.50 2.482 97.30
61 6/26/15 245.80 2.394 102.67
60 6/19/15 241.80 2.482 97.42
59 6/16/15 244.00 2.545 95.87
58 6/12/15 246.80 2.575 95.84

Scott,

How does the your mileage with the Tail compare to the same riding style without it?

What is your average commute speed? If I could guess, I would say you are running closer to 55mph.

Thanks, Jim.

[sendler]

I was at 93 mpg without the tail. 80% of the commute is highway with PnG and an average speed of 65 mph following something big at 2.5 seconds.

[sendler]

My last three tanks on the Honda CBR250R were 107, 110, 109 mpgUS. Interesting how the fuel economy has trended up from 98 earlier in the year when I first started riding it again after sitting for two years with the new tail and new chain. Does it take 8 80% tanks to get all of the stale fuel out? New Xring chains take 1000's of miles to break in? Worn Mobil 1 10W40 oil is more efficient after 5,000 miles?
.
Will do an oil change to Motul 300V 5W30 soon. But the weather will turn colder which works against fuel efficiency.
.
I'm also anxious to try the Michelin Pilot Street tires I took off of the Yamaha R3 on my CBR250R. I might get a few more percent with these long wearing commuter tires. The R3 lost some fuel efficiency when I switched to the more sport oriented Bridgestone S20Evo tires.

[jkv357]

Originally Posted by sendler

My last three tanks on the Honda CBR250R were 107, 110, 109 mpgUS. Interesting how the fuel economy has trended up from 98 earlier in the year when I first started riding it again after sitting for two years with the new tail and new chain. Does it take 8 80% tanks to get all of the stale fuel out? New Xring chains take 1000's of miles to break in? Worn Mobil 1 10W40 oil is more efficient after 5,000 miles?
.
Will do an oil change to Motul 300V 5W30 soon. But the weather will turn colder which works against fuel efficiency.
.
I'm also anxious to try the Michelin Pilot Street tires I took off of the Yamaha R3 on my CBR250R. I might get a few more percent with these long wearing commuter tires. The R3 lost some fuel efficiency when I switched to the more sport oriented Bridgestone S20Evo tires.

I'd be interested in knowing what type of gains it gives you, though with the weather change it may be hard to know for sure. I would expect to see some improvement in mileage over a 10W-40. Your 10W-40 M1 has most likely sheared down to a lower viscosity after 5000 mi in the CBR - but lower is better. There's not much capacity there, so the CBR works the oil pretty hard.

Motul 300V 5W-30 or Redline Ester 30 are good choices for the CBR IMO.

Are you running ethanol-free Regular?

[sendler]

Originally Posted by jkv357

Are you running ethanol-free Regular?

I pump E10 87 octane cheap stuff.

[jkv357]

Originally Posted by sendler

I pump E10 87 octane cheap stuff.

Non-ethanol gas will usually bump your mileage up - it could be pretty noticeable in the mpg range you are running.

Of course it costs more, but you'd have to calculate the % of cost increase vs the % of mileage increase to know if it's an advantage or not. Personally I always run ethanol-free 87 in the cycles no matter what the difference, but I can get it about a mile from work.

[sendler]

E0 is pretty much only sold at marinas in NY state. My bikes are all modern fuel injected now so I don't mind E10.