Sprocket Decision

[wooly72]

Hey guys, unfortunately in my area my baby is close to storage time since the weather will be changing dramatically soon. I want to get a few mods done to her before (and maybe even during) her stay in the garage.

Since I am putting new tires and exhaust w/ PCIII and o2 sensors, I decided to take off the EVAP canister (already did PAIR mods), K&N filter, Sarge seat, take off center stand, and now I have a decision about the sprocket/chain mod.

My question is: I am 255 lbs (have been since college) and don't see myself losing much weight, but I would like to get more accel and wanted to know which rear sprocket might help me lift the front end up some. Some guys say anything from going +2 to +4 on the rear will help achieve this.

I don't care about losing top speed, I don't really like going over 100+ anyway, but I would like better accel and I really love my VFR and don't want to trade her for a supersport.

Any suggestions would really be appreciated. Thanks.

[Guest]

yea, that'd up RPM at same gear / speed - the VFR isn't a high torque engine - new BMW 800 has more torque for example - so it's probably never gonna be a wheelie delight. Of course it's also gonna kill gas mileage cruising in 6 th gear, if that's a factor.

[Guest]

You would be surprised +2 on the rear what a difference it makes! And do not forget to add 2 links on your new chain otherwise it gets too tight.

[Guest]

Damn! +4 rear sprocket?! You plannin' on doin' some stuntin'? :pissed:

[Veefer800Canuck]

+3 in the rear is going to be almost directly equivalent to dropping 1 tooth on the front.

Approximately a 6% drop in gearing which will, of course, get you more ZIP!

[SEBSPEED]

-1, +2 is my favorite gearing combo on just about any bike! :thumbsup:

[Veefer800Canuck]

-1, +2 is my favorite gearing combo on just about any bike! :thumbsup:

As long as you're not doing 500 mile days, that is........

[wooly72]

Thanks for the info guys. I don't want to be doing any stunting, so maybe +4 isn't the way to go. Either +2 or 3 sounds more realistic I guess. Does the new chain / rear sprocket need to be 530? I didn't really want to have to change the front sprocket, unless I have too.

[Guest]

Just get another steel sprocket rear up 2 from http://www.sprocketspecialists.com/ in a 530

same as you have on the front. If you change one thing to 525 or 520 it all has to be changed.

It would be easiest to change one tooth on the front and be done with it, same amount of work

and would only cost about 14 bucks.

[Chev]

+4 up in the rear is not as much as you might think.

+4 up in the rear and -1 in the front is.

I think there might be some confusion on the board for this supject.

The equillivence is abou 3 in the rear to match 1 tooth in the front. So, your +4 sprocket is very close to a -1 front +1 rear combo. Keep in mind that making the front sprocket smaller will reduce chain life by some degree, and the stock front sprocket has a dampner in it. But, increasing the rear sprocket will increase rotational inertia as well as rotating mass from the extra links of chain.

My suggestion would be to go -1 in the front, and if you like it, buy a +3 or +4 rear sprocket the next time you change you chain/sprocket set and go back to a stock front sprocket to keep wear and noise down.

My $.02

[ronimalvfr]

Going down 1 in the front will also cause the chain to wear a little faster.

[Guest]

My 2 cents worth.

A smaller front sprocket will accelerate chain wear. The larger the front sprocket, the longer the chain will last.

Secondly, going up on the rear sprocket will cause the bike to handle better. I can't remember all of the technical explanation but it has to do with chain to swingarm angle, rear end lift, blah, blah, blah. A larger rear sprocket comes out of a corner better than a smaller front sprocket (handling wise).

[Baileyrock]

My 2 cents worth.

A smaller front sprocket will accelerate chain wear. The larger the front sprocket, the longer the chain will last.

True, but not a big deal

Secondly, going up on the rear sprocket will cause the bike to handle better. I can't remember all of the technical explanation but it has to do with chain to swingarm angle, rear end lift, blah, blah, blah. A larger rear sprocket comes out of a corner better than a smaller front sprocket (handling wise).

There will be No Change in handling whatsoever unless you change the wheelbase by moving the rear wheel forward or back. Yes if you run a chain/sprocket combo which causes you to pull the wheel all the way forward the bike will handle a fraction sharper(shorter wheelbase) but unless that is what your looking to do you would want a sprocket/chain combo that maintains stock wheelbase as much as possible.

Ideally adding teeth to the rear is the best way to make a change mechanically wise, but unless it's time to replace the chain and sprockets then I would just pop a 1 dw front sprocket on for $20 and be done with it.

I've run a 1 down front on my Vtec for over 40k now and love it, best performance gain(feel) IMO for the money, but I only use my VFR as a sports bike for twisty use only. I avg. 400 mile days and prefer the lower gearing 100% of the time for my type of riding. :thumbsup:

BR

[GP Paul]

Just my .02. I had a minus 2 on the front, but found the RPM range a bit too high for highway comfort. Went to -1 front and that's where I'll stay. (Also opted for Speedo Healer, as there was a significant difference.)

[Guest]

-1, +2 is my favorite gearing combo on just about any bike! :thumbsup:

+1

My 2 cents worth.

A smaller front sprocket will accelerate chain wear. The larger the front sprocket, the longer the chain will last.

True, but not a big deal

Secondly, going up on the rear sprocket will cause the bike to handle better. I can't remember all of the technical explanation but it has to do with chain to swingarm angle, rear end lift, blah, blah, blah. A larger rear sprocket comes out of a corner better than a smaller front sprocket (handling wise).

There will be No Change in handling whatsoever unless you change the wheelbase by moving the rear wheel forward or back. Yes if you run a chain/sprocket combo which causes you to pull the wheel all the way forward the bike will handle a fraction sharper(shorter wheelbase) but unless that is what your looking to do you would want a sprocket/chain combo that maintains stock wheelbase as much as possible.

Ideally adding teeth to the rear is the best way to make a change mechanically wise, but unless it's time to replace the chain and sprockets then I would just pop a 1 dw front sprocket on for $20 and be done with it.

I've run a 1 down front on my Vtec for over 40k now and love it, best performance gain(feel) IMO for the money, but I only use my VFR as a sports bike for twisty use only. I avg. 400 mile days and prefer the lower gearing 100% of the time for my type of riding. :thumbsup:

BR

Actually, adjusting the chain adjuster on a VFR WILL change the handling. Since the rear adjuster is consentric, turning it will change the swing arm angle and that does effect handling. Although, no offence intended, concidering the average riders ability they may never realize it.

[Guest]

And the bigger rear sprocket will effect handling on a race bike that is being driven hard out of a corner due to the increased leverage afforded by the larger pitch radius of the sprocket. (tends to squat the rear) It will NEVER be noticed on a street driven VFR. (No matter how hot a rider one thinks he is.)

Just dived the teeth of the rear by the teeth of the front to determine the final drive ratio and compare to other combos to find what you want. (or there is a chart in Vortex and Sunstars catalogs.)

[motogpfan]

-1, +2 is my favorite gearing combo on just about any bike! :thumbsup:

I just did the same last week,I likey :wheel:

Mike

[Daniel Paul]

-1, +2 is my favorite gearing combo on just about any bike! :thumbsup:

+1

My 2 cents worth.

A smaller front sprocket will accelerate chain wear. The larger the front sprocket, the longer the chain will last.

True, but not a big deal

Secondly, going up on the rear sprocket will cause the bike to handle better. I can't remember all of the technical explanation but it has to do with chain to swingarm angle, rear end lift, blah, blah, blah. A larger rear sprocket comes out of a corner better than a smaller front sprocket (handling wise).

There will be No Change in handling whatsoever unless you change the wheelbase by moving the rear wheel forward or back. Yes if you run a chain/sprocket combo which causes you to pull the wheel all the way forward the bike will handle a fraction sharper(shorter wheelbase) but unless that is what your looking to do you would want a sprocket/chain combo that maintains stock wheelbase as much as possible.

Ideally adding teeth to the rear is the best way to make a change mechanically wise, but unless it's time to replace the chain and sprockets then I would just pop a 1 dw front sprocket on for $20 and be done with it.

I've run a 1 down front on my Vtec for over 40k now and love it, best performance gain(feel) IMO for the money, but I only use my VFR as a sports bike for twisty use only. I avg. 400 mile days and prefer the lower gearing 100% of the time for my type of riding. :thumbsup:

BR

Actually, adjusting the chain adjuster on a VFR WILL change the handling. Since the rear adjuster is consentric, turning it will change the swing arm angle and that does effect handling. Although, no offence intended, concidering the average riders ability they may never realize it.

No offense, but I'm pretty sure that's what he just said...

[Guest]

And the bigger rear sprocket will effect handling on a race bike that is being driven hard out of a corner due to the increased leverage afforded by the larger pitch radius of the sprocket. (tends to squat the rear) It will NEVER be noticed on a street driven VFR. (No matter how hot a rider one thinks he is.)

Just dived the teeth of the rear by the teeth of the front to determine the final drive ratio and compare to other combos to find what you want. (or there is a chart in Vortex and Sunstars catalogs.)

Glad someone touched on geometry changes. As a street rider what I *have* noticed in changing the rear sprocket significantly (from 16/43 to 16/50, so +7 in the rear) is that despite what you would think (that it would wheelie a lot easier) it does not. I believe that this is due to the height of the leverage point in relation to the rear axle. Yes, the new chain is the correct length so the wheelbase is not affected. Strangely, dropping a few teeth off the rear on my old FJ1200 that only had a 5 speed and saw a lot of highway miles actually did make it wheelie easier once you got it out of the hole and rolling. Harder getting it 'out of the hole' off the line, though. Again, new chain in the correct length removes wheelbase as a possible contributor here.

Can't say I've noticed issues getting on the gas out of corners with the changes either up or down in the back.

BTW, I would *NOT* recommend this dramatic of a change (+7 in the rear) in gearing for anyone. The logic was that most bikes go -1/+2 which is equivalent to +5, and I added another +2 to the rear as this bike is a streetfighter and I figured I wouldn't miss the top end. I wanted to keep the front sprocket stock to preserve the chain life (520 conversion so not looking to be harder on it than I have to be). Highway trips are more painful from the revs than they are from the windblast, and I'm forever looking for sixth when I'm already in it. On top of that, first is gone before you can do anything with it.

Maybe just -1 on the front, or a simple +2 in the rear would be the best all round, perk it up without really messing it up, and minimize the geometry changes. My 1.94 cents (Canadian. Woo Hoo!)

[roadpupp]

Guys-

Sprocket specialist doesn't carry steel 530 45T (+2) rear sprockets.

Where does one get them?

Thanks

[Rice]

Guys-

Sprocket specialist doesn't carry steel 530 45T (+2) rear sprockets.

Where does one get them?

Thanks

Linky:

[DaBody1]

It would appear this would be a dead topic ..... but ... How much off the top end would one be losing by going -1, +2 kit?

I will be commuting on the interstate more this year then in the past. I still would like to be "zippier" off the light too.

Does anyone one know if there is a chart out there that shows the difference after gear change between MPH, RMP & Gear ratio?

How much will this type of change impact fuel economy?

Thanx!

[SEBSPEED]

If you're doing lots of highway, stick with just going -1 on the front.

[DaBody1]

If you're doing lots of highway, stick with just going -1 on the front.

Not to sound like a curious 2 year old but... Why is that? Thanx for the help!

[SEBSPEED]

Going up the additional teeth in the rear will raise your rpms enough to(possibly) make highway riding too 'buzzy', and it will hurt your gas mileage more than just going down 1 in front.

[DaBody1]

Going up the additional teeth in the rear will raise your rpms enough to(possibly) make highway riding too 'buzzy', and it will hurt your gas mileage more than just going down 1 in front.

Gotcha... thanx for the heads up. I think that I will take the modest approach and go 1 tooth down in front.