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Discussion Starter #1
I'm looking to get a bit more top end from the old girl...so that she isn't as buzzy at higher speeds.
At first I thought about going 14/47...that's only 3 teeth on the rear and shouldn't make that much difference. I remember trying 14/42 with my old '01 but it was awful; add a passenger and it was a slug climbing hills.
Then, I remembered that I have a 15T front that I order long ago but never used...
14/47 = .297
15/50 = .3
That's pretty close either way.
In a month or so, I'll be due for a new chain and sprockets anyway, so I thought I poll the studio audience and get their impressions/advice.
I do "mostly" hills and fire roads....no highway at all...some in-town.
Would I be better off going with the 15 tooth front, while keeping stock rear OR stick with stock front and smaller rear?
Is it less work for the engine to have a smaller front? Larger?
Having a larger front will decrease chain wear (ever so slightly)...
I plan on using steel sprockets and X or O-ring chain.


Opinions?
 

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BC,

Your old stock ratio is 50/14 = 3.571
47/14 = 3.357
50/15 = 3.333
If you maintain the same rpm as stock ratio at 50mph
The new speed would be;
47/14 3.571/3.357 = 1.064 x 50 mph equals a new speed of 53.20 mph at same rpm
50/15 3.571/3.333 = 1.071 x 50mph equals a new speed of 53.55 mph at same rpm

Or, and I don't know what exact rpm the original is at 50mph, but for math reasons lets use 6,000 rpm at 50 mph.
47/14 is a ratio change of 1.064 to 1, so 6,000/1.064 = a new rpm of 5,639 at 50mph.
50/15 is a ratio change of 1.071 to 1, so 6,000/1.071 = a new rpm of 5,602 at 50mph.

Now that I have bored you with the math, opinions as they say are like arseholes and everyone has one. But since you asked, and mine stinks more than most, you quoted {"I do "mostly" hills and fire roads....no highway at all...some in-town."}
My stinky opinion is that I know you like to explore, since I enjoy reading and pictures of your adventures (especially when you include co-ords), so I would guess you do quite a bit of slow riding as well and believe you will miss the stock gearing.
Marty
 

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BC,

Your old stock ratio is 50/14 = 3.571
47/14 = 3.357
50/15 = 3.333
If you maintain the same rpm as stock ratio at 50mph
The new speed would be;
47/14 3.571/3.357 = 1.064 x 50 mph equals a new speed of 53.20 mph at same rpm
50/15 3.571/3.333 = 1.071 x 50mph equals a new speed of 53.55 mph at same rpm

Or, and I don't know what exact rpm the original is at 50mph, but for math reasons lets use 6,000 rpm at 50 mph.
47/14 is a ratio change of 1.064 to 1, so 6,000/1.064 = a new rpm of 5,639 at 50mph.
50/15 is a ratio change of 1.071 to 1, so 6,000/1.071 = a new rpm of 5,602 at 50mph.

Now that I have bored you with the math, opinions as they say are like arseholes and everyone has one. But since you asked, and mine stinks more than most, you quoted {"I do "mostly" hills and fire roads....no highway at all...some in-town."}
My stinky opinion is that I know you like to explore, since I enjoy reading and pictures of your adventures (especially when you include co-ords), so I would guess you do quite a bit of slow riding as well and believe you will miss the stock gearing.
Marty
^^^^^^ what he said . Tw just isn’t made for high speed cruising.
 

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This is an age old dilemma with Dub riders that use it as a versatile machine. In the end game, it's all about compromise. If one gears the Dub with a tall set of gears for say, oh, maybe 85% street/distance riding and 15% for combo trail stuff, then one knows and realizes that that Dub's performance off road will be fairly reduced. Gear it the other way, 85% trail and only 15% street/distance, well, be prepared for the buzz in the bars (and everywhere else at least on mine) if you push it too much and too long on distance street driving.

But, based on ones weight, both body and Dubs, and if a goal is 50/50 in street and trail, then the stock gearing, as in a 14/50 to me, is a pretty good compromise. I'm 6' 2.5" and a mere 245 lbs. and the Dub actually does quite well both on the street and trail with my lard butt on there. But, and this is where I differ from a lot of Dub riders on here, I don't push my TW past about 45 mph. To me, that's tops for a little engine like that. But, that's my opinion. Others will have different thoughts. As for off road, yep, in first gear a lot, based on circumstances at hand. Once a slow section straightens out or there's a need, I grab more gears.

But, my Dub came with a 60T rear and stock front. Talk about SCREAMING on the street!! I'd hit 40 and you'd think I was doing 90 with little dub motor yelling at me to slow down. Hence, the change to a stock 50T rear and a new chain. So, this is one of those things that's really individual. What works for me, and or any one else, could be quite different for others. Good luck.
Scott
 

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It will make a 6.4 percent difference! ;)

However, if you still want to try one or the other, I would go with the 47 rear when comes time to change the set and stay with the 122 link chain. That way if you want to go back, all you have to do is get another 50 tooth to return to stock gearing and chain will still be long enough. Even though the back sprocket costs about three times the front, it is about four times easier to change. And like Scott said, tops for me is 45 but most of the time between 35-40 on the highway. I just don't get in a hurry anymore.
 

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More top end? Not really.
Slightly less buzzy per mph? Yes.
You plan to change sprockets and chain. So you are already going to do the front change.
You already have a new front sprocket (15 t). Put it on; while temporarily using the old chain and rear sprocket.
Just long enough to test it out. If you like it - buy another 55 tooth rear and chain to match.
If you think it is not enough; or too much - you can buy the new rear sprocket with another tooth more or less depending on your preference without having gone too far - along with the new chain to match. $0.00 cost to test it out.
 

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The 47T in the rear did ever so slightly help a bit with top-end. That's based on the cheap charlie made-in-china mini tach. It's accuracy is who knows?
I didn't want to go too far from stock because I did use my TW in the woods a lot.

Figure this, the bike set-up from the factory is almost perfect right in the middle, the engineers knew what they were doing. Am I glad I left the front sprocket alone and went to the 47T in the rear? Yes, but mostly because I got rid of the crappy stock chain that comes with it. Just a teeny-tiny bit of top-end that you might not even notice by feel.

But the chain (and the much better than stock JT Sprocket) are/were a big upgrade that you'll more than notice with how little you'll ever have to adjust your chain again. Really top-of-the-line equipment.
I went with a DID VX (X) chain BTW.
 

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Your weight has a lot to do with your decision. Gearing for a 250 pound rider is not going to feel the same as gearing for a 150 pound rider. I weigh around 160 and I like a 15/47 setup. With TW203/204 tires the TW is a very comfortable little street bike that can still survive on the trails. But then I cheat - I have a set of extra wheels with a 55 rear sprocket with stock knobby and Shinko 241 in the front for when I know I will be doing a lot of off road. It only takes about 45 minutes to change over.

I don't understand why you want more top end for "mostly hills and fireroads". For that I think stock or even lower would be best.
 

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I ran 15/47 on my 2006, and I weigh about 170. I got a lot more out of the top end but it had less acceleration up there. I didn't really feel like it took too much off the bottom end. If I had to describe that gearing, it felt like it made 1st to 4th gear wider, so that those gears had about the same range as 1-5 with stock gearing. 5th gear became sort of an overdrive gear, and I was able to do 75 mph on level ground without winding the bike out.
 

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The 6% rpm change in going from 50 to 47 teeth for any given over-the-ground speed comes at expense of low speed tractability, one of the TW's strong points.
Some don't mind this loss of performance.
Personally I prefer to accept a little slower highway speed if it means I will still be able to get up the steep off-road hills safely. Or put another way getting to a riding area quicker but then being unable to accomplish the ride comfortably is not to my advantage, but guess it means I could get home quicker with my tail between my legs.
My admittedly biased opinion is to go the other way exchanging time to get to the destination with ability to conquer the destination's challenges via 13x55 sprockets.
One of my TWs has dual front and rear sprockets for flexibility ranging from 15x47 to 13x55 sprocket combinations and it always lives with the 13x55 set-up.
Guess it all depends on how challenging the intended terrain is where you ride.
 

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My gearing compromise? 13/55 on one TW and 14/47 on the other TW. If I had only one TW I'd probably be changing the rear sprocket a lot (front sprocket is an even bigger pain than changing the rear IMO).

I do ride the 14/47 on trails as long as it ain't gonna be too steep, and I've come close to stalling a few times but, this was on a trail and not a logging or forest service road. My 14/47 was just to lower rpm's a bit knowing the TW isn't really gonna gain much in the top speed department.

I tried 14/45 once but it was more sensitive in 5th gear going up any uphill grade or into the wind and I ended up riding in 4th gear a lot.
 

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Don't hear much from others who have done the 223cc TTR motor swaps or 226cc 6-speed conversions. Guess we are by and large quietly giggling in the background. When I did my TTR engine swap using PlacerLode's output shaft extension I ended up with a lower first and a taller sixth gear than the stock 5 speed provided. Coupled with the additional torque afforded by the 12+ percent increase in displacement I ended up with a TW that gets nicely Jeepy creepy-crawly with it's ATV tire yet out accelerates the other TWs I've ridden with to comparable stock top speeds. My max indicated speed was a bit over 70mph but it was on a steep downhill with a tailwind while being chased by demons. :cool:

Somehow I imagine a TW in British Columbia would not want too long of legged gearing. Still want to be able to crawl over, around, or through whatever nature throws your way in beautiful B.C.
 

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A man convinced against his will, is of the same opinion still! ;)
 

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you're probably near me, I'm in Creston. If you ever want to try 15/47, come check it out on my bike.

edit: oh you're in the south WEST corner... maybe a bit of a drive then....
 

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I'm looking to get a bit more top end from the old girl...so that she isn't as buzzy at higher speeds.
At first I thought about going 14/47...that's only 3 teeth on the rear and shouldn't make that much difference. I remember trying 14/42 with my old '01 but it was awful; add a passenger and it was a slug climbing hills.
Then, I remembered that I have a 15T front that I order long ago but never used...
14/47 = .297
15/50 = .3
That's pretty close either way.
In a month or so, I'll be due for a new chain and sprockets anyway, so I thought I poll the studio audience and get their impressions/advice.
I do "mostly" hills and fire roads....no highway at all...some in-town.
Would I be better off going with the 15 tooth front, while keeping stock rear OR stick with stock front and smaller rear?
Is it less work for the engine to have a smaller front? Larger?
Having a larger front will decrease chain wear (ever so slightly)...
I plan on using steel sprockets and X or O-ring chain.


Opinions?
I went 15/49 and am totally happy with the ratio.
 
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