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Discussion Starter #1
Was looking at some sprockets and saw a 525 15-tooth front sprocket for a triumph that looked compatible to the bobber. Read in some old dead forums 10+ years ago that dropping more than one tooth up front was ill advised but never met anyone who actually had a bad experiance themselves. Increased chain wear seems likely because of the tighter tolerance on the front sprocket radius, but I had heard RUMORS of chains snapping but never first hand accounts or even a photo so was sceptical of heresay and false trends without numbers behind them. I figured chains have come a long way in 20 years and a quality 525 chain has some room to grow on a 500pound bike with 80 Tq and Hp but what's your opinion?
 

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Welp never mind that... although it looked compatible measurments dont lie. Guess all i get is one tooth knocked out for being a jerk.
View attachment 42524 View attachment 42525
Aaaaaah, well that's a shame. I was interested in the result of this little experiment as I seem to be obsessed about changes in gearing at the moment.
You are far from a jerk as you've saved someone else the trouble of ordering a front sprocket that simply won't fit. ?
 

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Sprocket gearing!! .

At best your frazzle everyone's brain.

At worst your gonna start WW3.

I'm staying out of this lol. (for now ;))
 

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It's hard to ignore all the different opinions.

I've never had a chain snap on me personally.

I've changed loads of sorockets etc. Some with new chain. Some without new chain. It really makes no realistic difference.yes it might wear a couple thou/inch different but it's a bike not an f16.

Loads of bikes I've slapped a rear sorocket only on. Wore No different to changing both sprockets and chain.

I'm prob gonna get hammered for this but hey. The facts dont lie
 

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Discussion Starter #7
Sprocket gearing!! .

At best your frazzle everyone's brain.

At worst your gonna start WW3.

I'm staying out of this lol. (for now ;))
Didn't mention oil brand/blend, change interval, or the controversial oil weight change in a high heat or cold environment, now that just gets people worked up. Just seems like a 15 tooth gear made to work with a given chain size and crank size would be a viable option. Had to look through ALOT of sprockets but found one that fits our bike thats used on the CBR1000RR Fireblade. It has 130HP and 95 torque and uses a 525 chain as well. Seen this sprocket on a tiger 1050 as well so sounds like a winner and schematics look identical
If this superbike can use the sprocket size with the same chain I feel safe using it as well. Will let you guys know IF I order and how it goes. With a 14T available maybe somebody wants to go roadhouse and just knock out 3 teeth.
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My question is why do you feel the bike needs that much lower hearing? I can see adding a tooth to the rear for a different feel or possibly 2 if you really wanted to get lower...but dropping 2 on the countershaft equates to a big drop in gearing. I am guessing you must not spend much time at highway speeds.
 

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My question is why do you feel the bike needs that much lower hearing? I can see adding a tooth to the rear for a different feel or possibly 2 if you really wanted to get lower...but dropping 2 on the countershaft equates to a big drop in gearing. I am guessing you must not spend much time at highway speeds.


Finally!!! Someone else is thinking for themselves and talking sense!

You might wanna read the thread. "RK spockets any good "
 

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Discussion Starter #10 (Edited)
Seen plenty of
My question is why do you feel the bike needs that much lower hearing? I can see adding a tooth to the rear for a different feel or possibly 2 if you really wanted to get lower...but dropping 2 on the countershaft equates to a big drop in gearing. I am guessing you must not spend much time at highway speeds.
Seen plenty of 16/39-40 set ups that everyone really seems to endorse and enjoy. Lets do some math. Those have a gearing of 2.4375 and 2.5 , the gearing of a 15 tooth front sprocket with 37 rear is only 2.4666 right in the middle of those two. Doesn't seem that extreme to me, not even close to to the 2.65 I see on the HP crank on a Thruxton.
Pros: one sprocket replaced without needing a second larger rear sprocket that would need a chain to be extended beyond factory.
Cons: possible premature wear... if the Honda fireblade with 50 more Horsepower and torque can use it I'm sure its not pushing this part to it's limits in my bike.
As far as why I want lower gearing this bike can hit top speed in 4th gear , dropping the gearing isn't going to effect top speed on the bike and give me some better 4th-6th pulls without having to shift down when I almost get cut off and ran over by a truck or car with some 19 mom texting. I get 45mpg putting around to work and back so if it drops to 35-40 and my bike is more fun for ME to ride then this will be a massive success in MY eyes. Insert my bike in place of the one ring.
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This probably wont end with me dehydrated missing a finger on the side of a volcano...
 

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I find myself on the open roads, freeway, and tollways where crushing 80-85 for several miles is normal. I could never see a need or want to have lower gearing.
 

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I find myself on the open roads, freeway, and tollways where crushing 80-85 for several miles is normal. I could never see a need or want to have lower gearing.
That's what it's all about , modifying the bike or not to individual needs. I live on an island 25 miles across , no motorways and one stretch of dual carriageway. I rarely ever go above 80 mph as the roads aren't long enough! ? So if I can get a bit more drive out of the corners and it makes me smile doing it then I'll try anything once....except folk dancing. ?
 

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Discussion Starter #13
They have alot of highways here but I rarely use them do to non signalling and dangerous drivers in thick traffic. Too many close calls when I go out on them! I take back roads with lights most the time as my farthest drive is to the dealership and thats only 45 minutes. However when on them the extra pep would make me feel at ease. The bikes range is pretty limited already so a few lost miles wont bother me much, part of the bobber style package in my mind. I really just want a little more pep without having to change rear sprockets and chain right now so this fits the bill perfectly for me.
 

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Discussion Starter #14
Did a little division and with two teeth gone up front the sprocket teeth will have 12% more often contact with the chain per crank rotation. That probably equates to the same percent factor of wear as well.
 

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Dropping serious teeth imo, would make it pull more in higher gears without changing down gear Granted.
But really your just changing down gear permanently. Lots of talk about 6th gear pull. What about the 1st gear your gonna almost loose.

Lots of posts want more 5th/6th gear pull for overtaking but don't ride highways much. :unsure: :unsure: :unsure: :unsure:

Is rather just click down a gear on the shifter to overtake and have the full range of gearing when I'm not.

I don't ride motorways but big A roads at 50-70mph. Wouldn't want that engine buzzing even more at those speeds. I like a cruiser that can cruise at low rpm. Then stamp it down to liven it up. It's a bobber!!!
 

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Discussion Starter #17 (Edited)
Like I said 2.466 gearing is right at the sweet spot between a 16/39 and 16/40 sprocket setup . It gets you there with less hard to find 39 and 40 rears to buy and replace while still using a stock chain with the factory wheel clearance on the rear fender.

So 20 bucks gets me the gearing a 195 dollar kit would afford me at the measly cost of a 12% increase in front sprocket wear.

I usually ride in 4th cruising around and this is going to effect that gear substantially and from what I hear about the gear ratios in this range its great with minimul and acceptable effect on MPG at least for me anyway. Dont plan on trying to ride this bike to Sturgis anytime soon...
 

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Discussion Starter #19
Hi, this other thread goes into details. I've drop one on the front and added a couple in the back (if I recall correctly). Geared to the moon?
Saw that and commented there, nobody had used a -2 front setup as a triumph specific part isn't made . Thats why I started started this one with a catchy name to see if anyone had specifically used a setup with a compatible size sprocket. Pretty sure rogan.mcgillis is running a 15T but unsure of branding or part number.
 

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Discussion Starter #20
So got my sprocket in the mail today, problem is it has a lip. Going to try to fit it this next week or so but if there is an allignment or clearance issue I may need to get it machined down to fit.
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