Originally Posted by Tweety

That happens at the point where one gear actually turns into another... Ie with 15/43 you have turned 2 gear into 1 gear from the stock gearing... And you have effectively created a gearbox with 0-1-2-3-4-5 instead of 1-2-3-4-5-6... Ie the gears are shorter, because the engine spins up faster, and you have just moved the entire chain down one step... First gear, now "0", is almost useless, because you cannot give the bike any throttle in this gear without lofting the front wildly...

Originally Posted by Tweety

Lol... You know I live for discussions...

Back to it... The difference is that 16/43 gives you a net gain... It does all you say you want out of it... You get to rev it out and reach the the theoretical top end, and you still have a usable 1st gear... 15/43 looses the first essentially...

And yeah, the difference is actually not far from 150 -> 120... 16/43 hit's a theretical 167 at redline in 6'th... 15/43 is 149... And I can personally vouch for the fact that a stock bike can reach redline, albeit I can't say for sure on rev limiter or actual roadspeed at those revs...

But, i can say that with very little work done to the engine, like a lighter flywheel, and stacks and such, you should be capable of combining that with 16/43 and actually get usable redline and increased acceleration, without loosing at the other end ('cept money)...

I'n my particular case, it's fairly moot... I have 120+ bhp at the rear wheel, and I can most definetly hit both redline and the limiter in all gears with stock gearing... Yeah, I have verified that... And I highly doubt I'll be more than marginally behind a stock engined VTR, regardless of gearing... Even the pesky liter 4's have to work a bit to outdrag me... (not too hard though)...

When I did try 15/43 it made my first gear entirely useless... And the bike tried to come up in 3'rd unless I pushed it down...

Originally Posted by 8541Hawk

Well I guess you felt this little gem was just fine to throw out



but become a bit upset when you get it tossed back at you?

From my side, this is just like the last thread on this subject. Yes I am defending my opinion using facts and examples. You defend your side with feelings and conjecture. When I don't agree and the facts back me up, you try to turn the thread into a pissing contest.

I guess after 2 threads worth of trying to explain the whole thing and showing the facts behind it. At this point, I am getting a bit tired of hearing that the math and\or facts mean nothing and it just feels better.

I'll ask again, how? I'll give you one last example. Up to now all of these have somehow ended up as standing start acceleration or top speed at red line. Neither of which is "normal" street use.

So for this one you have 2 bikes, one with 15\43 and the other 16\41 (with all other variables the same on both bikes).

Now you are on your favorite back road coming up to a corner. The bike with 15\43 is in 4th. So to be turning the same (or close enough to be called the same for this example but if you really need we can crunch the actual numbers if you need) RPM and to be running the same speed the bike with 16\41 gearing will be in 3rd. With me so far?

Now the 15\43 bike down shifts 1 for the corner. The 16\41 does the same. Now the bikes hit the apex and accelerate out. As both bike are going the same speed, turning the same RPM and have the same (once again the actual number can be posted but for all practical purposes they are the same) overall gear ratio, which one will accelerate faster out of the corner?

As I see it there would be no difference.

If you can explain how one could be faster than the other at this point, I would be very interested in hearing how that could be.

This is one reason why I say that 15\43 is a poor gearing choice. In normal riding conditions you gain nothing over the stock gearing and make too many compromises at the same time.

You even admitted it the last time we went over this :


Which is fine if that is what you want but to suggest the gearing to someone else and leave that little factoid out is doing them a disservice.

There are also other draw backs to 15\43. You may claim you never use 6th or ride open roads but most people do. I know I end up on the freeway or a Hwy going to my riding spots or even running out for an ice cream all the time.

I these situations running the higher final drive gives you lower engine RPMs and chain speed. Which not only gives you loner chain, sprocket and engine life, you also get better fuel economy.

All things you give up with 15\43 while gaining nothing.

Then again, I'm just a big meanie and am just trying to force things on people.......

Originally Posted by Furrybiker

16/43 does it for me, the bike feels better at very low speeds in town, less slipping of the clutch and few more revs to lessen the chance of a low rev stall, and it runs well at 80 to 120 on the motorway (allegedly!).

Originally Posted by uchi

haha yeah you do love them, especially with noobs. lol. your bike is the exception as it makes oh about 20 more hp than everyone elses on here, lol. so we need to make up for it somewhere

ill agree first gear the front end is dancy and she comes up part throttle without issue but throttle control makes me a better rider plus i dont drag race the old girl that much i more throw it around a corner here and there. now if i could get more power without breaking the bank id drop the gearing to a simple -1 setup and leave it at that, but as much fun as these bikes are they are greatly under powered in stock form. speaking of power, the mods you listed, how much do you think theyre worth? i wouldnt mind a few extra ponies. maybe some cams if i blow the old girl up this year

Originally Posted by nath981

Same **** different thread, but i'll weigh in again. haha. I've rode OEM for about 9 years, then 520 15/43 for a year or so , and 520 15/44 since, and i'm happy with the latter set up. Granted i don't tour and i avoid straight roads obsessively. When I have ridden cross state, or anywhere for that matter, it takes me forever because I connect every bent road possible to my destination and back.

You can do the math and all the rational solutions possible to determine what's the most efficient, fastest, best compromise, etc., but if that was the definitive answer for everyone, Rossi wouldn't have to do any on-track testing.

Listen to advice, yes, and then do your own testing. If you're not willing, you can just read and do what others determine what is right for you, but in the final analysis you'll find that one size doesn't fit all.

Originally Posted by killer5280

But if you like 15/43 or 15/44, for whatever reasons, you're stupid. The math says so.

Originally Posted by killer5280

But if you like 15/43 or 15/44, for whatever reasons, you're stupid. The math says so.

Originally Posted by uchi

now listen here you big meanie. haha.
i can see what youre saying, so if you come into a corner at 9000 rpm in 2nd gear, and i come in at say 8000 rpm in third, you need to shift as soon as you leave the corner and i can drag third out a bit longer cause its third gear and not the short second youre stuck with through that corner, see what im getting at?

Originally Posted by Tweety

Buuut... One thing though... It's one thing to like that gearing... It's another to say that it is more efficient and will make your bike accelerate faster... That's simply not true... In that case, the math says it wont... And whatever you think about math, it just so happens that in terms of things you can measure, it trumphs feeling...

Originally Posted by 8541Hawk

+1
I'm still waiting to hear how when you have 2 bikes with the same overall gearing (gearbox + final drive) how one can accelerate faster than the other.

I guess I'm just a big meanie, know it all for asking that question and have been vilified numerous times for it.

Actually what I believe is happening is that when folks install the 15\43 gearing they now think they will need to rev the bike more.

What this does is actually get them up to where the real power is, so now they think the bike is quicker.

Originally Posted by Tweety

Well, dude in your case, we don't need math to figure that one out...

J/K... I like you man...

Buuut... One thing though... It's one thing to like that gearing... It's another to say that it is more efficient and will make your bike accelerate faster... That's simply not true... In that case, the math says it wont... And whatever you think about math, it just so happens that in terms of things you can measure, it trumphs feeling...

Originally Posted by uchi

I guess the thousands of people who re gear their cars and bikes are wrong. If a 10 second drag car ran the gear it does and then dropped to an insanely low gear where it crossed the finish line in second gear instead of 5th. Would it still run 10s in the quarter mile? No. You're wrong.

Originally Posted by uchi

Any time you put a taller gear in you accelerate faster and loose top speed.

Originally Posted by uchi

Riddle me this. Why did my mustang run nearly a. Full second faster in the 1/4 mile after its regear?

Originally Posted by uchi

Riddle me this. Why did my mustang run nearly a. Full second faster in the 1/4 mile after its regear?

Originally Posted by Tweety

This way re-gearing is usefull, 15/43 isn't unless you do it for a very specific purpose like a very tight and twisty track that has no straights what-so-ever and need that fraction you gain in 2-3-4'th gear...

Originally Posted by killer5280

Those 3 gears are the gears I am in 95% of the time when I ride on my favorite roads, so, yes, I like the fraction I gain in 2nd, 3rd and 4th and will gear for it. 2nd gear with 15/43, in spite of what has been said here, is not the same as 1st gear with 16/41 gearing. Not really even close.

Here are some captures from the spreadsheet I use to calculate gearing so everybody can do their own math. I didn't write the spreadsheet and I haven't checked them carefully, but the formulas appear to be correct. If they aren't I'm sure I will hear about it. Tire circumference makes a big difference.

Originally Posted by 8541Hawk

By using your spread sheets isn't 1st-2nd-3rd with 16\41 actually lower overall gearing than 15\43 in 2nd-3rd-4th?

So yeah you got me with the "they are the same comment" but actually I was rounding off in your favor.

So by using your numbers wouldn't a stock geared bike running from 1st -5th out accelerate a 15\43 equipped bike in 2nd-6th?

As long as the rider could shift from 1st-2nd the stock geared bike would have lower overall gearing in the first 3 gears and equal gearing in the last 2 gears. It would appear to me that the stock geared bike would be quicker in this situation.

Wouldn't it be a better solution to either work on shifting the bike or maybe installing a FP shift star kit? For me the shift from 1st to 2nd isn't really all that big of a deal.

Still that is just another thing you leave out when you guys recommend the 15\43 gearing.

That is my whole point of this. Yes run whatever you like but it is a great disservice to the members of this list to recommend something without also stating the drawbacks and shortcomings of the modification.

Originally Posted by 8541Hawk

+1

I'm still waiting to hear how when you have 2 bikes with the same overall gearing (gearbox + final drive) how one can accelerate faster than the other.

I guess I'm just a big meanie, know it all for asking that question and have been vilified numerous times for it.

Actually what I believe is happening is that when folks install the 15\43 gearing they now think they will need to rev the bike more.

What this does is actually get them up to where the real power is, so now they think the bike is quicker.

Originally Posted by 8541Hawk

How does being 1 gear different in the gear box in any way equal being 3 gears different as you used in your example?



Well first of all a Taller gear would make you accelerate slower and have more top end but I know what you are saying.....

The problem is you also need to figure in the gearbox not just the final drive ratio. Once you get to the point that the overall gear ratio is the same as the overall ratio of the higher geared bike one gear different in the gearbox, you have gone too far and defeated the purpose of re gearing. I don't know how to make that thought any clearer.

So running a lower gear will give better acceleration. Though it is possible to go too far when dealing with a multi speed gearbox.

Originally Posted by 7moore7

I think the argument can be made that you can absolutely floor your 'stang in first gear without fear of it flipping over backwards- in other words, you can use all of the acceleration that the lower gearing gives you.

With the VTR, there is no way you can WOT first gear without it flipping over backward in 15/43... I actually have problems doing this with stock gearing although that can be attributed to rider ability haha! So in a basic sense, if you can't open the throttle up all the way, you aren't making use of all the torque that the motor can give you.

I'm not familiar with newer trucks, but back when I was working summers with an old neighbor, he had an old F-150 with a standard transmission. Driving through the fields, he always started the truck in 2nd gear. 1st gear was so low that it was of no use to him when it was just the truck. The torque of the motor could easily handle just the truck and he didn't have to waste time shifting into second if he started it there. It was still a useful gear- he put in in first when he had a trailer attached or just needed to go at a slow steady pace (us walking along side it, etc...). It was just a "low" gear.

Anyway, the way I imagine in my head what is going on, is that you're creating a "low" gear (for hauling hay or four-wheeling) when you gear it at 15/43.

Originally Posted by killer5280

This quote is from a response to uchi, but I will use it here. Those 3 gears are the gears I am in 95% of the time when I ride on my favorite roads, so, yes, I like the fraction I gain in 2nd, 3rd and 4th and will gear for it. 2nd gear with 15/43, in spite of what has been said here, is not the same as 1st gear with 16/41 gearing. Not really even close.
I don't care at all about top speed and I don't care much about first gear. 15/43 allows me to avoid the clunky 2-1 downshift and clunky 1-2 upshift when I'm riding fast just about entirely.
I don't care about fuel mileage, although I might start soon, and I don't care about chain and sprocket wear.
I have never claimed that this was anything but my opinion and I have never said that there is one optimum gearing combination for everyone. I don't try to force my opinion on anyone and I don't impugn anyone's character because of a stated preference for this or that gearing combination.
I like 15/43. It suits me fine. Could I ride my favorite mountain roads as fast with some other combo? Probably.

Here are some captures from the spreadsheet I use to calculate gearing so everybody can do their own math. I didn't write the spreadsheet and I haven't checked them carefully, but the formulas appear to be correct. If they aren't I'm sure I will hear about it. Tire circumference makes a big difference.

Originally Posted by uchi

you hit the nail on the head, gearing up will get you into the power faster and will make the bike feel as if its making more power when in fact its not, its gearing thats making you accelerate faster, no matter how you look at it, a re geared bike will accelerate faster than a stock geared bike. theres no disputing that. hell the best way to look at this is like this.

two identical bikes start at 60 mph in 6th gear, one of them is geared 15/43 the other 15/44. without downgearing which one will hit 140 mph faster? 15/44 every time

Originally Posted by uchi

it was a big example i was getting at, i was trying to enlarge the situation to show what im trying to say. my stock mustang would cross the traps in third gear, after the re gear id cross in 4th. the extra shift didnt slow me down enough to make it an issue.

i know exactly what youre saying in the gear box thing below, and i understand what you mean, my point is that even though you need to shift sooner, youre still going through each gear a little faster with a lower top speed, but itll still pull harder.

heres the bottom line guys, our bikes in stock form dont make the power to see redline in 6th gear. tweety claims to have seen it but he found a big hill or cliff or strapped a rocket to his back, the swedes are clever with how they do things, so he doesnt count, lol. theres no point in running gearing on the bike that you cant fully use. both gear setups are fairly close where it shouldnt make that much of a difference. a tooth in the back wont be nearly as noticeable as 1 in the front. i like the gearing my bike uses because i can come out of a corner in the wrong gear at a lower rpm and itll still have enough go to not cause me to bog or anything. as stated in another reply thats the nature of these motors. if i come into a decreasing radius turn and i come into it at 9000 rpm and come out of it at 6500 rpm i can still get on the gas and have her wake up and go, thats the beauty of being geared so hot. i dont need to down gear mid corner, cause we all know these bikes will lock up the back tire on a hard high rpm down gear, ive done it alot at the track. so id personally prefer to have a gear setup that may or may not just barely top out 6th gear on the open hiway. why have gearing you cant take advantage of? now for those of you who do hiway riding, yeah you wont benefit from my gear setup. i dont like the fact that my bike revs 1000rpm or so higher than stock, but i stay off the hiways with it and if i need to take it someplace an hour or two away for a day of riding ill trailer and save the tires. unless the roads going there are twisty. i dont enjoy getting sore *** from riding the hiway for hours on end. but thats me

so, run what you like, its clear this is one of those discussions that wont ever end because we all have our opinions on what works for us. hell my track bike is going -1+4 but its also getting a 190. but my home track on the honda i was hitting about 120- 130 mph on the main straight, so im fine with that much gear on the little 600.

so fellas, thanks for keeping it civil, and before i end this, i wanna leave you with a parting gift.

yellow bikes are the fastest, the end