Jump to content

-1/+2 520 conversion considerations


jhenley17

Recommended Posts

Did this today. I didn't really get to stretch her legs, but I thought two things might interest those considering. First, the gear indicator will not know what planet it's on. Zero worky. Second, you'll rev a bit higher. I know that's obvious, but just for example, VTEC engagement in 6th gear went from ~94 MPH to ~82 MPH.
 
The gears certainly do feel tighter, I would say an absolute must in urban areas, but you won't like it if you do a lot of highway miles.
 
The only non-stock setup I could find was Superlite through Sprocket Center. I think if I keep this bike a while, I'll have to order custom-made sprockets.
 
Excuse the dirt. I've had four days off in the past six weeks and rarely see my home in daylight.
 
8213d141f66d4cc0cee244c2e50b3224.jpg460833c88f0f044535cb8038d0375229.jpg



I think a black chain would have looked better, but they were out of stock and I couldn't wait any longer. The black nuts from Sprocket Center were easily marked up by my socket. I'm probably going to try some gold ones since I couldn't get the black chain that I wanted, probably from Driven or Pro Bolt.
Link to comment
Share on other sites

  • Member Contributer

Looks like an interesting mod. Be very keen to know if it does effect your gear position indications. I'll have a guess that it won't considering there a three discrete gear sense switches telling the ECM what gear you are in! I can change to any gear at any speed or RPM and the indications are correct!

Cheers.

Grum

Link to comment
Share on other sites

So far, ~50 miles, it hasn't corrected itself, just a flashing "-." When I first got on, it was showing gear numbers, but within a few hundred feet, it was gone. The speedometer seems accurate, so whoever said it was run off of the ABS ring was probably right. For the gear indicator to work, though, I'm thinking it would need some kind of electronic box to trick it into seeing correct RPM relative to speed for that gear, and I'm doubting that exists. To me, it's a small nuisance overshadowed by the livelier feel of the engine.


Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

  • Member Contributer
2 hours ago, jhenley17 said:

So far, ~50 miles, it hasn't corrected itself, just a flashing "-." When I first got on, it was showing gear numbers, but within a few hundred feet, it was gone. The speedometer seems accurate, so whoever said it was run off of the ABS ring was probably right. For the gear indicator to work, though, I'm thinking it would need some kind of electronic box to trick it into seeing correct RPM relative to speed for that gear, and I'm doubting that exists. To me, it's a small nuisance overshadowed by the livelier feel of the engine.


Sent from my iPhone using Tapatalk

 

That's a real bummer. No doubt about it - speed comes off the rear wheel ABS ring.

It seems an utterly ridiculous system, that you have three independent switches sending the specific code of what exact gear is selected to the ECM, why on earth does it need to complicate the gear indication further by somehow also comparing RPM to Speed, makes no sense at all, shame about that!

Cheers.

Link to comment
Share on other sites

I guess it's supposed to be a self-checking system. They didn't have much foresight as there are plenty that like to change sprockets for either lower revs on the highway or better acceleration. I guess it would also be possible to bypass that check, but also something that probably doesn't exist. It did try again this morning to go off of the switches once, but after a few seconds in sixth gear, it went back to blank.

Another thing I realized this morning, with VTEC coming on in the 80s, if you cruise at that speed, your fuel mileage is going to take a hit. It pulls so much better in top gear, though, from all speeds. It doesn't feel like I'm going as fast as I am, though. I guess maybe the higher revs with less wind are throwing me off.


Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

6 hours ago, Grum said:

 

That's a real bummer. No doubt about it - speed comes off the rear wheel ABS ring.

It seems an utterly ridiculous system, that you have three independent switches sending the specific code of what exact gear is selected to the ECM, why on earth does it need to complicate the gear indication further by somehow also comparing RPM to Speed, makes no sense at all, shame about that!

Cheers.

 

There is more going on than it appears to the eye. If you put a quickshifter on, it will also not work if the gear indicator stops working.

 

The ECU self calibrates the gear indicator using RPM and speed as well as the independent switches however it also seems there is more going on.

 

Also remember that when in 1st gear, when you let the clutch out, the RPM increases by 200 rpm as well. I'm wondering what else the engine does relying on certain data being correct.

Link to comment
Share on other sites

I have the stock chain and -1 on the counter shaft.  Everything works.  Better 1st gear ratio and better 6th gear - only slight change.  I am very happy and recommend this change.

Link to comment
Share on other sites

  • Member Contributer

This sounds/looks pretty cool. I may have to change my chain/sprockets to 520 when the chain is

due again. Wonder if I'll be able to find a 45 tooth 520 rear sprocket. I had to have a custom sprocket

made for my Yamaha a few years ago.

Link to comment
Share on other sites

  • Member Contributer
4 hours ago, FJ12Ryder said:

This sounds/looks pretty cool. I may have to change my chain/sprockets to 520 when the chain is

due again. Wonder if I'll be able to find a 45 tooth 520 rear sprocket. I had to have a custom sprocket

made for my Yamaha a few years ago.

 

You certainly can, I went with 17/45 520 on my 5th from Sprocket Center.

Did a 500 mile ride in the twisties on the weekend, feels good.

 

 

Link to comment
Share on other sites

As I said in the OP, if you're in the US, Sprocket Center seems to be the only route for non-stock sprocket sizes. They only come in 520 pitch. I wasn't particularly worried about saving ounces, but 520 was the only option and this bike isn't that powerful, so I'm good with it. Stock is 16/43. You have the options of 15, 16, and 17 for the front and 43 or 45 for the rear. I went for the lowest possible gearing (15/45), which made a pretty drastic change to my cruising RPMs, but it pulls pretty hard in any gear now. My priority right now isn't really highway cruising, but I wouldn't want to do several hours of interstate above 80 mph with this setup.

 

The gear indicator is still trying to work, but I guess the variation from stock is just too far for it to be happy.

 

 

Sent from my iPhone using Tapatalk

 

Link to comment
Share on other sites

There are some things to consider here!  

The '14 VFR peaks at 10,000 RPMS even,  and holds that output til 10,500 or so before it drops off.  
Looking up the trusty gear commander,   and the specs on the '14 's drivetrain at 16 and 43 the VFR800's reported top speed of 138 mph happens pretty much at the top of Fifth gear leaving 6th gear about 10% down on peak power @ around it's reported top speed.  If the bike was making 115-120 HP that myself,  and all the other guys scrounging for a real header,  intake, and tuner setup This would be awesome because you might just see the 150MPH 10500rpm's in 6th gear.

 

However at bone stock tune That's 9500 RPM's or so in 6th.  Good for highway mileage,  Not so sure about acceleration or top speed characteristics though.

at -1T front we see a big shift and the 10500 6th gear comes down to about 144-145 mph.  which might be a better tune for the basic bolt on crowd,  PCV,  some mufflers,  flappers gone,  ect.

But from a motorsport standpoint,  1 down and 2 up is the usual,  and for the '14 on paper seems to be a knockout upgrade.  

10500 in 6th gear,  138 mph.   I'm betting the accelleration would be vicious compared with stock gearing.

To combat the idea of this being a no brainer upgrade though:
The math says you will hit Vtec in 6th,  also known as THE DEATH OF ALL GAS MILEAGE HOPES,  at least 550 rpms sooner.  
I'm seriously considering going 1 down and 2 up on my 14.  but we'll just see.  Has anyone else

done this yet?

2014_VFR800hp_dyno.jpg

vfr800 GC.jpg

Link to comment
Share on other sites

On 10/31/2017 at 7:49 AM, jhenley17 said:

As I said in the OP, if you're in the US, Sprocket Center seems to be the only route for non-stock sprocket sizes. They only come in 520 pitch. I wasn't particularly worried about saving ounces, but 520 was the only option and this bike isn't that powerful, so I'm good with it. Stock is 16/43. You have the options of 15, 16, and 17 for the front and 43 or 45 for the rear. I went for the lowest possible gearing (15/45), which made a pretty drastic change to my cruising RPMs, but it pulls pretty hard in any gear now. My priority right now isn't really highway cruising, but I wouldn't want to do several hours of interstate above 80 mph with this setup.

 

The gear indicator is still trying to work, but I guess the variation from stock is just too far for it to be happy.

 

 

Sent from my iPhone using Tapatalk

 

I am in the US and have -1 front sprocket with the stock 530 chain.  You can purchase non-stock sprockets on Ebay for 530 chain.

Link to comment
Share on other sites

  • Member Contributer

JHenley, how much livelier does your bike feel for the typical 0-60/80/100mph type runs?  If we assume your stock 8th gen does 0-60 in 3.0 and 1/4 mile in 11.4 sec (as per zeroto60times.com), what would you estimate the new gearing would allow for roughly?  I do a lot of 0-100mph runs so I'm very interested in your mod.  I don't do much highway cruising and hardly ever use 6th gear so I'm thinking I wouldn't see many negatives from doing this.  Can you still hit 100 mph in 3rd gear?  My favorite thing to do is wind it up through 1st, 2nd, and 3rd and then back off once I hit 100mph as seen in the vid below:

 

 

Link to comment
Share on other sites

  • Member Contributer
1 hour ago, GatorGreg said:

JHenley, how much livelier does your bike feel for the typical 0-60/80/100mph type runs?  If we assume your stock 8th gen does 0-60 in 3.0 and 1/4 mile in 11.4 sec (as per zeroto60times.com), what would you estimate the new gearing would allow for roughly?  I do a lot of 0-100mph runs so I'm very interested in your mod.  I don't do much highway cruising and hardly ever use 6th gear so I'm thinking I wouldn't see many negatives from doing this.  Can you still hit 100 mph in 3rd gear?  My favorite thing to do is wind it up through 1st, 2nd, and 3rd and then back off once I hit 100mph as seen in the vid below:

 

 

See if you go to gearing commander and put in the sprocket sizes your question will be answered. In fact you can put in any sprocket size you like and it will give you the answers. 

Link to comment
Share on other sites

I'm not quite sure where I'm at at the top of each gear yet, I'm still getting used to it. I know 55 in sixth is ~4500 RPM. I'm not the most sensitive to minute changes, but I feel like I get up to speed much quicker when I'm not behaving antisocially. As for full throttle runs, I haven't really done enough with it to give you a good answer.


Sent from my iPhone using Tapatalk

Link to comment
Share on other sites

  • Member Contributer
18 minutes ago, jhenley17 said:

I'm not quite sure where I'm at at the top of each gear yet, I'm still getting used to it. I know 55 in sixth is ~4500 RPM. I'm not the most sensitive to minute changes, but I feel like I get up to speed much quicker when I'm not behaving antisocially. As for full throttle runs, I haven't really done enough with it to give you a good answer.


Sent from my iPhone using Tapatalk

 

Thanks, I look forward to seeing your updates as you get more time with it.

Link to comment
Share on other sites

  • Member Contributer
27 minutes ago, jhenley17 said:

I'm not quite sure where I'm at at the top of each gear yet, I'm still getting used to it. I know 55 in sixth is ~4500 RPM. I'm not the most sensitive to minute changes, but I feel like I get up to speed much quicker when I'm not behaving antisocially. As for full throttle runs, I haven't really done enough with it to give you a good answer.


Sent from my iPhone using Tapatalk

It will accelerate quicker with the new set up 

Link to comment
Share on other sites

  • Member Contributer
29 minutes ago, fink said:

It will accelerate quicker with the new set up 

 

Golly gee really?  What makes you think that?

 

 

 

 

 

 

 

:tongue:

Link to comment
Share on other sites

 

Right, I'm just trying to quantify changes as much as I can as I'm no poet or great communicator.

 

I don't know how much help it'll be, but I'll put the GoPro on in the next few days.

Link to comment
Share on other sites

  • Member Contributer
11 hours ago, GatorGreg said:

 

Golly gee really?  What makes you think that?

 

 

 

 

 

 

 

:tongue:

:wheel:   Don’t think it, I know it.  

Link to comment
Share on other sites

23 hours ago, DriverDave said:

FYI - the stock chain on the 8th gen is actually a 525.  The 6th gen came with a 530.

Yeah, you're right.  It's a 525.  If your chain is still good.  Go down 1 tooth in the front.  When you need a new chain, put the old front back on and go up 3 teeth in the back.  Easy and inexpensive mod.  

Link to comment
Share on other sites

  • Member Contributer

I remember, not very long ago, when none of my bikes had gear indicators.  Somehow, I was able to ride just as well as I do now.

 

I can even ride without turn signal canceling devices.  Simple is good sometimes.  The gear indicator is a good thing IMO.  

 

Riding a motorcycle well, takes quite a bit of muscle memory, eye, rest of body coordination, and instinctive thinking, acting and reacting.  Maybe that's why 

some of us enjoy riding.  If we're still alive (I am right now), if might be because riding a motorcycle will strengthen one's defensive riding / driving skills and instincts.  

I wonder how many riders and drivers are killed and hurt by "drivers" using cell phones.  That's as big an issue killing people as the latest "opioid epidemic" bandwagon politicians seem to enjoy riding on.  I'm going to ride a VFR in the mountains today.....; )  Yay.  That's the only reason I own one.  

  

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy.