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Sprocket changes to make the bike torquier

26 posts Started 19 Feb 2015 Last recovered post 21 Feb 2015 Wayback Machine snapshot 21 Jun 2015

#1

I've run a -1 front for over 100k miles and would never go back to stock. The bike just feels better and for <$30 and 30 min you can decide if it works for you. 

Go For It!   :wheel:

Actually @ 100k miles I'm trying a 520 set-up for the first time.

#2

...I don't play in the gear box nearly as much, ...

And there was me thinking that using the gearbox (and clutch) made the whole ride more absorbing and involved and it wasn't a proper bike unless you used the gearbox (and clutch) a lot. 

So you could always try using the gearbox more, or just buy an automatic - whatever you do, don't buy a DCT!

Seriously, the only way you'll get a VFR800 to equal or surpass the performance of a bike more than 200cc bigger is to *charge it (* = super/turbo/NOS).

I tried a tooth change on my 5th Gen years ago and as well as making the speedo read even less accurately, there were more downsides than upsides; unsettled, more vibration at cruise speeds, worse mpg were the main.

I don't doubt that others have enjoyed the change, just didn't work for me.

#3

When I bought my bike, it came with a 16/45 (5th gen 17/43 stock).  The previous owner had done some track time back in IL and maybe that was the correct gearing for the track he was using (?).  Both sprockets were still in good condition, but the chain was exhibiting the 'red dust' (bike had sat for a few years and the previous owner had moved to a Harley for his wife's enjoyment). so I just changed the chain (found a great buy on Ebay).  I believe it was 110 links (stock size) and it fit just fine. 

I do get a vibration starting around 6500 rpm @ an indicated 85-88mph. No bad, but noticable.  More in the pegs than the bars (Heli-bars with Throttlemeister)

It does change your speedometer.  I figured out over the years that it's probably 10% off (using many traffic radars, at various speeds/gears).  In Colorado, most jurisdictions won't pull you over if your 9mph or under, the posted limit and I've passed many, many police cars and radar traps doing less thatn 10mph over and never been stopped.  I drove to work for years traveling past state troopers, county sheriffs and city police @ an indicated 67-69mph in a 55mph zone and never was stopped.  I figured- 55 + 9 = 64 + 6(10%) = 70.  I wanted to be safe, so I kept it @ 67-99.  There were several discussions on this site about figuring your speedometer change, but I think they all assumed the original Honda speedo was dead on.  Of course you could go the GPS route or the PwrCmdr/Speedohealer route.

That bring up the question, if your speedo is 10% inflated, is your odometer not also inflated by the same amount?  I've put about 10,000 miles on the bike since I bought it, so have I really only gone only 9000 miles?

I would recommend you try the -1 front first and if that doesn't get you where you want, then put a 45 on the rear and see what you think.  Someone else may know for sure, but I believe the stock chain will still work with this combo.  BTW my sprockets and chain still look in good condition @ ~10,000 miles.

#4

So is the conclusion then than it's better leaving the sprocket sizes standard on the 5th gen? 17/43

#5

So is the conclusion then than it's better leaving the sprocket sizes standard on the 5th gen? 17/43

I don't think there is one conclusion that works for all.

Some like it, others don't. Each to their own. Vive la difference!

#6

5th gen front = 17t, 6th gen front = 16t  rear on both 43t. Now why did Honda do that ? Oh to compensate for the extra weight of the 6th gen, so just buy a 6th gen front sprocket for your 5th gen or an after market 15t for your 6th gen. job done, been running 16/43 or 16/42 on my 5th gen for years, love it.

So just to address this question a bit...  The internal transmission gear ratios are different between the 5th and 6th gen. They are the same for first and second gear but for third thru sixth gears they are not. Sixth gear for the gen 6 is an "overdrive" where the 5th gen is still above 1:1.  So even with the more aggressive 16/43 sprocket set up for the 6th gen., it has a reduced rpm in sixth gear by comparison with the 5th gen.  But i think the conclusion from Mohawk is right. Honda wanted to give the 6th gen more overall ratio spread to keep the heavier bike feeling sporty.

I wonder what the 8th gen has done? I haven't looked into that at all.

#7

One last thing to think about. I've heard going -1 up front causes premature chain wear. Going +1 or +2 in the rear means you'll probably have to get an aftermarket sprocket and it'll probably be made of aluminum. An aluminum sprocket doesn't last anywhere near as long as a (stock) steel sprocket. Ask me how I know.

Theoretically a smaller sprocket will increase the angular momentum of the chain and cause accelerated wear. Going from a 17 to a 16 is going to make very little difference and probably not result in any increased wear. If you went to a 13 or a14 that would be a different story.

You can get a steel aftermarket rear sprocket with 45 teeth. I got mine from Sprocket Center, so you're not limited to aluminum.

A stock speedometer is about 7% optimistic, but the odometer is on the money. I went to a 45 tooth rear sprocket and my speedometer is now 12%-14% optimistic, and my odometer is now about 7% optimistic. I didn't really feel like spending big bucks on a Speedo-Healer so I just mounted a bicycle computer and use that for my speedometer/odometer now. It's not lit for night riding, but I don't ride much at night, so no biggie. Here's what it looks like:

[image: Cockpit.jpg]

#8

Okay yes, I realize that changing gearing does not change the engines output. But, here is your chance to save the VFR from the chopping block. I LOVE the triple in my Tiger 1050 because it has torque. I don't play in the gear box nearly as much, it feels smoother, and I can pull out of the corners with less effort. Yes, it has 20 something pound feet more torque. However, I am curious if changing gearing on the Viffer will allow me to better use the power available, maybe to mimic what I like in the Tiger. My concern with this approach is to get the effect I want I may be running 6K RPM+ on anything above 60 or so MPH, which, while I'm sure the engine can take, I would rather not abuse the bike. What works for you guys? 

Thanks, as always, for the advice!

PRB


#9

Change the front sprocket for one with 1 less tooth than stock.

Feels like more power. Accels easier. I did this to mine years ago, and have kept it that way since.  :beer:


#10

You could lower the gearing a little, so your revs would be higher for a given speed in a given gear, throttle response will usually be better too.

However, the SSSA will limit the amount of teeth you can add to the rear & removing teeth from the front sprocket is only feasible for a couple of teeth anyway.


#11

I went with a 45 tooth rear sprocket and it is perfect for me. Quicker acceleration at lower rpm, and that suits me just fine. I no longer feel like 1st gear is too high for practical use. It works with the stock length chain which is an added benefit.


#13

This will kind of give you an indication of what effect changing sprockets will have. Notice -1 up front has a greater effect than +2 in the rear. Simply going +1 in the rear will be noticeable but probably won't yield the result you're looking for.

The higher the number in the gear ratio column, the lower the ratio. The lower the ratio, the greater the mechanical advantage you'll have and the quicker your bike will accelerate. The drawbacks are, the greater the change in ratio, the more your RPM's are going to go up and the more top end speed you'll lose. And here's something nobody's mentioned: the greater the change in gear ratio from stock, the more your speedometer will be off.

Attached Images

  • [image: Gearing.png]

#14

Change the front sprocket for one with 1 less tooth than stock.
Feels like more power. Accels easier. I did this to mine years ago, and have kept it that way since.  [image: emoji481.png]

+1

Forget all the angular Physics and theoretical overkill.

-1 up Front is the least Expensive way to make your VFR feel that little bit quicker off the Jump... From stopped at lights or out of corners.

You will use a tad more gas at Same Speed over Same distance as Someone w stock Gearing. If Cruising mention your VTEC will come on at Some 5-7 km/h less than stock, so ask Buddies to cruise According to your Pace or you'll be in VTEC and they won't.

Instead of 265 km/h top Speed it will be slightly less but still very Illegal. This bike Takes ages to get to top Speed anyway due to ratios. It still gets to 200 km/h in next to no Time.

Chain Life May Suffer slightly too but most people Don't Look after their chains anyway and I still get way more out of mine.
#15
Always heard to always start with the front sprocket for what your looking for. Think even in the new Cycleworld they discuss this as well in the ask the mechanic section.
Good luck
#16

5th gen front = 17t, 6th gen front = 16t  rear on both 43t. Now why did Honda do that ? Oh to compensate for the extra weight of the 6th gen, so just buy a 6th gen front sprocket for your 5th gen or an after market 15t for your 6th gen. job done, been running 16/43 or 16/42 on my 5th gen for years, love it.

Don't go any lower than -1t on the front or the chain will eat the chain slipper on the swingarm, followed by the swingarm pivot ! 

You should (if you can find them) be able to go as high as 48t on the rear, but may run out of chain at that point !

Remember you want the axle on the rear as close to the 6 o'clock position when possible. You can move it towards the 9 o'clock position to get more chain length, but that lowers the rear.

Incidentally, anyone that wants a lower ride height rather than using lowering plates, could just invert the axle holder to the 12 o'clock position & lose 2-3" off the rear ride height. Might have to check the brake torque arm does not foul & that the chain guard still clears the chain.


#17

One last thing to think about. I've heard going -1 up front causes premature chain wear. Going +1 or +2 in the rear means you'll probably have to get an aftermarket sprocket and it'll probably be made of aluminum. An aluminum sprocket doesn't last anywhere near as long as a (stock) steel sprocket. Ask me how I know.


#18

Well that's a lot to take in... It seems like a cheap experiment so  I may drop -1 in the front and see what happens. 

-PRB

...where do I find a 16 tooth front for a 5th gen?


Edited by PirateRiderBen, 20 February 2015 - 11:51 AM.
#19

Well that's a lot to take in... 

...where do I find a 16 tooth front for a 5th gen?

The 5th. gen and 6th gen are the same except for # of teeth. So you can just look for a 6th gen & the standard will be 16 teeth. For an aftermarket part I'd suggest the AFAM brand. I've found them to be good. IIRC the part number is 20602-16. 

If you want to retain the rubber vibration isolator then you'll have to buy a Honda OEM part. I looked on Parzilla.com and see their price is $45.50 for that sprocket. I'm sure an AFAM is cheaper but probably not by much.

Mark

#20

I'm a fan of Sprocket Specialists, but I can't say they are any better than other options out there.  What I do like about them is there selection is pretty complete.

#21

Some of you guys need to be a little patient with Ben (he's a little slow because he went to ECU). :laugh:

#22

Some of you guys need to be a little patient with Ben (he's a little slow because he went to ECU). :laugh:

Alright now....  :sleep:

#23

^ I lived in Raleigh 10 months (June '13 - March '14). As much as I liked North Carolina, it's unlikely I'll ever live there again.

#24

I love western NC, can't beat the mountains for riding. 

-PRB

#25

All of North Carolina was great. There's no part of it I didn't see while I was there: Deals Gap, Asheville, Charlotte, Greensboro, Winston-Salem, the OBX, Wilmington, Fayetteville, Raleigh, Chapel Hill, Durham, ........you name it. My mother visited me the month before I left and I took her to see the Biltmore Estate. I never would have gone to see it had she not been there but I admit it was pretty cool. We took an entire tour of it (i.e. indoors and out).

I saw a fair amount of South Carolina, too. This isn't a very good picture, but that's the Columbia skyline in the background.

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  • [image: 5 - Columbia, SC.jpg]
#26

I dropped one tooth up front on my last VFR and while acceleration was much better, I hated having my speedometer showing a much higher speed than I was going and once up to highway speed, I was always trying to shift into another gear when I was already topped out. That sprocket didn't last 4 months before I put the stocker back in. That being said, it is a super easy swap if you want to try it out. Just loosen your chain as much as possible, pull the cover of the front sprocket, remove/replace the sprocket, and re-tighten the chain. DONE in ten minutes.

End of thread · 26 posts recovered Wayback Machine snapshot 21 Jun 2015