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Discussion Starter #41
I think this is a difference between perception and reality. TTP has this stock hp curve:

A stock Bonneville makes something like 45hp (according to this curve) at 5K rpm and over 60hp at 8K. The entire point of downshifting is because you make more power at higher revs. Maybe there's something seriously wrong with your bike, or is it a 270-deg crank bike (America/Speedmaster/Scrambler?), but a normal stock Bonneville/SE will be way quicker if kept above 5K rpm at all times. Even a 270-degree crank bike still makes more power after 5K up to 7K... but the 360-deg bikes increase pretty linearly right up to the rev limiter (and beyond if you bump the rev limit).



I bet if you put a stopwatch on it, you'd find that's objectively incorrect. Downshift to 3rd gear and it'll fly.

This is why I mentioned about the perception of turning the throttle and having a feeling of a surge of "power" without downshifting. That's what I think most people are looking for when asking for "more power". And BTW that's why there's bikes that make a totally unusable amount of top end power ... it's because what the buyer really wants is 50 hp at 3500 rpm, not 10K rpm. But 50hp moves the bike just as much no matter the rpms.



airbox baffle removal, bellmouth inlet, TEC 2-1 exhaust, TTP tune 2 2-1 (with my own ECU tweaks...). I did remove the SAI and evap stuff but that has no effect on performance. I doubt my mods have added more than 7 hp, but I have not had it on a dyno. But I have pinged it off of my 8500 rpm rev limiter in first gear several times. I assure you it doesn't stop pulling after 5K. It doesn't have that kind of peak-rpm drop off like my other bike does.
Yeah, I see what you're saying, and the dyno doesn't lie, it just feels like I don't accelerate as fast from 5500-8000 rpm as I do from say 2500-5000. I thought that's why people switched out the stock 865 cams with the 813's.

I have the 360-degree engine. Maybe what I'm noticing is the torque drop from 6000-8000 rpm?

Because of that feeling, I rarely ever went past 5000 rpm. I'll try winding her all the way out next time I ride. It probably is my perception.

Not doubting what you're saying, I'm just trying to understand how this all works. Maybe I need to try downshifting more and stay closer to redline when passing?
 

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Discussion Starter #42
I reread your posts a few more times, and I think I understand what you're saying. I guess I just need to wind her out more.
 

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Yeah, I see what you're saying, and the dyno doesn't lie, it just feels like I don't accelerate as fast from 5500-8000 rpm as I do from say 2500-5000. I thought that's why people switched out the stock 865 cams with the 813's.
The 813 cams are most likely going to give more power at higher rpms and potentially less midrange torque.

I have the 360-degree engine. Maybe what I'm noticing is the torque drop from 6000-8000 rpm?
Remember HP = Torque * RPM / 5252 ... even though torque falls from 6K to 8K HP actually increases because revs rise faster than torque falls.

Because of that feeling, I rarely ever went past 5000 rpm. I'll try winding her all the way out next time I ride. It probably is my perception.

Not doubting what you're saying, I'm just trying to understand how this all works.
I think it's either something is broken, or just your perception.

And perception can be a very powerful thing. For example, a lot of people seem to think when they hear or feel an engine revving high that it is "straining" or "working hard". Like somehow by revving you are forcing it to perform past its limits. So this mental response might cause you to feel uncomfortable, or like the engine is straining, when you rev it, thus changing your perception of whether it is actually going faster.

Lots of things affect perception like this. Some people used to tell me my Miata (mildly warmed over 2000 Miata that looked like a race car) felt "anemic". But it would do 0-60 in under 6 seconds. Same people would hop in a C3 Corvette and think it was fast, but my little "anemic" Miata would blow away a C3 Corvette in every measure. But this is all because of perception.

If you never rev your Bonneville over 5K then no wonder you feel like it needs more power. You're using literally half of the available power.
 

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FYI, this post illustrates what you might expect from the cams:

Less midrange, nearly all of the gains above 6K rpm. It'll go faster as long as you wind it up.
 

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Discussion Starter #45
The 813 cams are most likely going to give more power at higher rpms and potentially less midrange torque.



Remember HP = Torque * RPM / 5252 ... even though torque falls from 6K to 8K HP actually increases because revs rise faster than torque falls.



I think it's either something is broken, or just your perception.

And perception can be a very powerful thing. For example, a lot of people seem to think when they hear or feel an engine revving high that it is "straining" or "working hard". Like somehow by revving you are forcing it to perform past its limits. So this mental response might cause you to feel uncomfortable, or like the engine is straining, when you rev it, thus changing your perception of whether it is actually going faster.

Lots of things affect perception like this. Some people used to tell me my Miata (mildly warmed over 2000 Miata that looked like a race car) felt "anemic". But it would do 0-60 in under 6 seconds. Same people would hop in a C3 Corvette and think it was fast, but my little "anemic" Miata would blow away a C3 Corvette in every measure. But this is all because of perception.

If you never rev your Bonneville over 5K then no wonder you feel like it needs more power. You're using literally half of the available power.
OK, I understand now. Thank you for taking the time to explain it to me!

I'll hold off on swapping the cam for now and just do the other power mods along with revving the bike to redline when accelerating.
 

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Off topic slightly , many years ago I recall watching a presentation about Kawasaki in which we were shown how the engines were tested . Z900 the original one , was run for 24 hours at the red line on a dyno of some sort . I would think things have moved on in the last 45 years but would imagine that the testing is no less severe . Moral of my story is don't be afraid of the red line .
 

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But if I buy an 1800cc Harley, think of all the leather and dealer t-shirts I would have to buy just to get a return wave on the road. Not to mention that HOG membership and those pins. If you thought modding a Bonneville was throwing away money.... Mister you have no idea.
 

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Changing gearing doe
Off topic slightly , many years ago I recall watching a presentation about Kawasaki in which we were shown how the engines were tested . Z900 the original one , was run for 24 hours at the red line on a dyno of some sort . I would think things have moved on in the last 45 years but would imagine that the testing is no less severe . Moral of my story is don't be afraid of the red line .
I don’t care about the rev line. It’s the rev limiter that slows you down.
 

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all mods affect resale. they almost always make it worth exactly the amount you spend on them less. its hard to sell modified anything because peoples tastes vary so much. and if you trade it in to a dealer theyll take off the value however much it costs them to bring it back to stock.
 

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Hmm, not sure things are as cut and dried as you imply, Kahless.

When I bought my '04 Daytona, in 2007, it had aftermarket clipon risers, aftermarket seat, and the previous owner had installed a TOR muffler. The dealer left them all on, and they are part of why I chose that bike. The seat and risers in particular made my 955i into a bike I could tour on.

I'd say the more extreme your mods are, the better the chance you're actually hurting resale value and the odds of finding a buyer. Keep it reasonable, and it can help. I've read lots of reviews and buyers guides about older bikes that say things like "look for one with these changes already done: __."

So the oh-so-helpful-answer is "it depends." But again, if this is your #1 concern, something is wrong. Buy something you love, do what you want, and worry about resale later. Unless you've got the vehicular attention span of a butterfly on espresso.
 

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Hey all,

Been thinking about getting my 2013 Bonneville T100 ready for this riding season, and I was thinking about doing some upgrades.

She's all stock right now, so I was going to add a better exhaust (Gasser Customs) along with the TTP EFI Stage 2 Power Induction Kit.

But if I'm going to change the intake, exhaust, and the tune, I figured I might as well go the whole nine yards and drop in a high performance cam too.

Also change the suspension and handlebars, add rearsets... you get the idea.

All these mods are going to get me close to $3000, and I was wondering if changing the bike this way would make it harder to sell in the future. Would it affect the resale value?

I like my Bonnie, just want it to have a little more power and be sportier feeling. I'm not sure if it would be better to sell it as it is and just buy something else.

A bike with mods may not appeal to everyone. For those that it does appeal to, they cost of the mods will never be recouped. It will just make the bike more attractive to a potential buyer that likes the mods.
 

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all mods affect resale. they almost always make it worth exactly the amount you spend on them less. its hard to sell modified anything because peoples tastes vary so much. and if you trade it in to a dealer theyll take off the value however much it costs them to bring it back to stock.
When I traded my T120, the Triumph dealer offered me the KBB value on the stock bike. Nothing extra for shields, luggage, custom suspension or exhaust. Worse with private buyers. Could be my area (Reno) where there’s generally little interest in used Triumphs, I got no more than KBB for a Rocket with dynamite custom paint, Jardine performance exhaust (which was no longer obtainable), dyno tuned 152 hp/162 ft lbs, custom Progressive suspension, luggage, and several windshields. I had one serious buyer on that bike.
 
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