I replaced my chain recently, and dropped down to a 15 front sprocket (and love it BTW !!!) and I was wondering if it efffects the speedo/odo accuracy?
I know our speedo's are generally 8% off, but since I did the sprocket change I'm closer to 9-10% when compared to my GPS, and my mileage has gone up from 41 to 45 mpg...
Oh yeah, you're going to be waaay optimistic on the speedometer, and the odo will be off a bit too. Probably part of the reason your fuel mileage went up, or rather looked like it went up. In all likelihood it went the other way with the amount depending on how much hiway you're doing.
I also dropped one tooth in the front. I expect mileage gains like you because acceleration is "easier" on the bike. We all know acceleration is the gas guzzler for MPG. With -1 front you dont need to really rip the throttle for the same acceleration as before. I cannot check my mpg anymore b/c my od is messed up by the sprocket change. i assume you are getting your mpg from your gps trip tracker...
I dropped to a 15 tooth sprocket on my 5th gen and the only down side is higher RPMs at high speeds. But I have notice no change in fuel mileage and still am impressed that my 98 VFR runs so well and gets around 38mpg with 82k miles on it. I thought the 6th gen VFRs had a stock 15 tooth front sprocket.
If you are using your odometer to make mileage calculations they will be inaccurate. You should use a GPS odometer to correctly calculate mpg if you change sprocket gearing.
I haven't checked mileage with my GPS yet. I was going off the odo, That's why i was curious about the 15t effecting my readings.
I have a phone app that tracks a trip, (my tracks) I just keep forgetting to turn it on before a ride.
Capt Bob, 16/43 is what comes stock on a 6th gen. I wanted to go with 16/45 but the 45 rears are hard to get ahold of?
I haven't checked mileage with my GPS yet. I was going off the odo, That's why i was curious about the 15t effecting my readings. I have a phone app that tracks a trip, (my tracks) I just keep forgetting to turn it on before a ride.
Capt Bob, 16/43 is what comes stock on a 6th gen. I wanted to go with 16/45 but the 45 rears are hard to get ahold of?
Thanks for the replys
Your speedo is now off 20% and your odometer is so far off, MPG numbers are inaccurate, dont bother trying to calculate
I started looking for a 45 tooth sprocket for my '99 back in May. No joy. Sprocket Center finally got some in near the end of July. I found several places that had 45 T sprockets for the 6th gen though.
I put a cheap bicycle computer on mine so I have an accurate speedometer. Odometer isn't that big of a deal to me.
I replaced my chain recently, and dropped down to a 15 front sprocket (and love it BTW !!!) and I was wondering if it efffects the speedo/odo accuracy? I know our speedo's are generally 8% off, but since I did the sprocket change I'm closer to 9-10% when compared to my GPS, and my mileage has gone up from 41 to 45 mpg...
That mod usually puts the speedo of another 8% off (14-16% total) and now the ODO is reading around 8% faster equaling your presumed mileage gain.
In an attempt to gain better fuel mileage I conducted an experiment in tire pressure. With the preload correctly set for sag while on the bike, I would run several tanks at differfent air pressure intervals. I was sure to ride as consistently as I could, and found that as much as 1lb of pressure had an impact on mpg. Just food for thought.
there are 932582953809238509 variables in MPG. if you changed the psi in your tires, then drove in a straight line at 55mph for 150 miles with NOTHING different, then you can really tell. PSI does make a difference overall though. higher pressure = better MPG... but dont go too high cause you need the softer tire for grip and flex
I took a ride to Orlando this afternoon to see a friend and according to my VFR trip odo it was 216 miles round trip. My GPS claimed 204 miles which I know is more accurate, as my truck odo sais the same when I make that trip. So yes, 8% sounds about right,
I used 4.6 gals = 44 mpg...Not bad seeing that the 15t cog kept me in the 6000-6700 RPM range while cruising.
With stock gearing I would average 40-41 mpg religiously hand calculated. ???
the 15t cog kept me in the 6000-6700 RPM range while cruising.
You 'cruise' pretty fast :tour: I'm at 90-100 mph at that rpm range... just as I hit vtec in 6th gear.
You either keep up or get ran over by tourists staring at palm trees :smile: LOL, My Vtec comes in about 68-6900, & It's my subtle reminder to slow down. :fing02:
Tire wear makes a big difference in speed and RPM as well. I had Q2's that were so flat i was mm from a blow out. I was doing prob 80 at vtech kick in in 6th gear. Now with new PR3's i am much MUCH lower RPM at those speeds! (15t front sprocket). If you have a worn tire it makes a difference...
Tire wear makes a big difference in speed and RPM as well. I had Q2's that were so flat i was mm from a blow out. I was doing prob 80 at vtech kick in in 6th gear. Now with new PR3's i am much MUCH lower RPM at those speeds! (15t front sprocket). If you have a worn tire it makes a difference...
I changed my worn out Battlax BT016 a week before I did the chain & sprockets. It was worn flat, I bet it did have an effect on the gearing as well. Went with the BT023 touring tire this time round. Hoping to get over the 4000 miles that the soft tire gave me.
Did the same change-1 tooth upfront. Installed a speedo healer and calibrated it to ensure accuracy (compared with gps and the speed is dead accurate as is the odometer) Milage slipped roughly 5%. partly due to the fact that I like the improved get up and go, more happy time with the throttle open. Less time on the highway, more time powering out of corners. There is no improvement by increasing the rpms- effectively dropping a tooth increases the rpms. For some reason I can not get into my fuelly log, where I kept the before and after records.
End of thread · 18 posts recoveredWayback Machine snapshot 1 Dec 2014