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I have a 2016 Heritage with 103 high output motor. My buddy just bought a 2019 street glide 114 motor. What can I expect in "on ramp" accelarations? He has a bigger motor, I have less weight. gearing? Thanks.
 

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Are you asking who's bike is going to be faster? Most likely his...bigger engine, and newer engine design. M8 114 should put out about 90 hp and 120 ft lb. Your TC103 should do 75hp and 93 ft lb, according to my very limited Google search.

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weird member
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It's really hard to say. How high an output?

There's some calculators where you can input all the data and get an idea of roughly what your absolute best possible time might be... but you have to know your peak rw torque and HP AND at what RPM those numbers occur, all gear ratios (in the tranny and the primary and final drive), total weight with rider, rear tire diameter...

 

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old scoot coot
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Are you asking who's bike is going to be faster? Most likely his...bigger engine, and newer engine design. M8 114 should put out about 90 hp and 120 ft lb. Your TC103 should do 75hp and 93 ft lb, according to my very limited Google search.

Sent from my SM-G965U using Tapatalk
and once again. their is no substitute for cubic inches. the one with the biggest hammer wins.
 

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weird member
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Although displacement matters, it also depends how it's built. An 80" Evo can do 90/90 rwt/rwh with some headwork, compression and cams. I've even seen a dyno sheet of an 80" Evo that did over 100/100...
evo80w6h-6.jpg
But, that's also not gonna happen with "simple/basic" bolt on kits, takes some extra work.

There is more to power than just raw CI. But, even a heavier bike with higher cubes can still be faster despite more weight. The weight actually doesn't matter as much and 100 lbs doesn't make as much a difference as people think when they ignore engine power.

There's a power to weight ratio. So even if his bike is 100 lbs heavier, it's still a 114" against a 103" and I'm betting he's got a better power to weight ratio, and those 11 extra CI probably make more than enough difference of 100 lbs extra weight (if it's that much). I mean I don't really know, could crunch typical numbers in the calculator to get the ratios but... then I would have to do research.

And I'm not saying weight doesn't matter at all, but we are talking street cruisers here, not race bikes.

Plus, that's beyond my experience level anyway. I've built one engine ever, I have no real experience with baggers, no race experience, 0 experience with TC or M8 engines...
 

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old scoot coot
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Although displacement matters, it also depends how it's built. An 80" Evo can do 90/90 rwt/rwh with some headwork, compression and cams. I've even seen a dyno sheet of an 80" Evo that did over 100/100...
View attachment 781527
But, that's also not gonna happen with "simple/basic" bolt on kits, takes some extra work.

There is more to power than just raw CI. But, even a heavier bike with higher cubes can still be faster despite more weight. The weight actually doesn't matter as much and 100 lbs doesn't make as much a difference as people think when they ignore engine power.

There's a power to weight ratio. So even if his bike is 100 lbs heavier, it's still a 114" against a 103" and I'm betting he's got a better power to weight ratio, and those 11 extra CI probably make more than enough difference of 100 lbs extra weight (if it's that much). I mean I don't really know, could crunch typical numbers in the calculator to get the ratios but... then I would have to do research.

And I'm not saying weight doesn't matter at all, but we are talking street cruisers here, not race bikes.

Plus, that's beyond my experience level anyway. I've built one engine ever, I have no real experience with baggers, no race experience, 0 experience with TC or M8 engines...
stoplight to stoplite sprints the dynas and soft tails probably going to beat the pants off us hog drivers. i've still got kid in me i'll give it a shot even just to see what ya got! 🤠
 

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old scoot coot
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2,892 Posts
Although displacement matters, it also depends how it's built. An 80" Evo can do 90/90 rwt/rwh with some headwork, compression and cams. I've even seen a dyno sheet of an 80" Evo that did over 100/100...
View attachment 781527
But, that's also not gonna happen with "simple/basic" bolt on kits, takes some extra work.

There is more to power than just raw CI. But, even a heavier bike with higher cubes can still be faster despite more weight. The weight actually doesn't matter as much and 100 lbs doesn't make as much a difference as people think when they ignore engine power.

There's a power to weight ratio. So even if his bike is 100 lbs heavier, it's still a 114" against a 103" and I'm betting he's got a better power to weight ratio, and those 11 extra CI probably make more than enough difference of 100 lbs extra weight (if it's that much). I mean I don't really know, could crunch typical numbers in the calculator to get the ratios but... then I would have to do research.

And I'm not saying weight doesn't matter at all, but we are talking street cruisers here, not race bikes.

Plus, that's beyond my experience level anyway. I've built one engine ever, I have no real experience with baggers, no race experience, 0 experience with TC or M8 engines...
 

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The M8 heads will out flow the TC heads, especially on the top end.

Tommy's new bike gets real damm close to mine straight out of the box on torque.
With a Stage 1, it might even beat it.
 

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old scoot coot
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The M8 heads will out flow the TC heads, especially on the top end.

Tommy's new bike gets real damm close to mine straight out of the box on torque.
With a Stage 1, it might even beat it.
cool. i haven't really ridden it yet except to gas station and back. but it does feel tourqie that is my favorite part. if that thing will get even close to keeping up with yours, then moco did good. as good as it seems now at least i think i won't be in a hurry for stage one. if flash ran as hot as yours, then fury would probably get lonesome. 🤠
 
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