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Discussion Starter · #1 ·
I have just gotten my 07 Bonnevile and love it. I wish it had a tach,
but since it doesn't I wish someone could relate gear usage to mph ranges. I would with more usage develop that feel for the appropriate gear --- but in the mean time I want to avoid "lugging down" or "over revving". Your help would be appreciated.
 

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You need to know what size the front sprocket is (17T,18T or 19T). If your bike is stock it should be 18T, that would be at 70mph you should be about 4000rpm from what I remember (I put on the 19T).BTW these engines like the rpm's
 

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Handy Spreadsheet

If you follow this link
http://www.triumphrat.net/twins-technical-talk/98571-handy-bonneville-spreadsheets.html you will find a ZIP file. Download it and extract the "Speed and RPM" Excel spreadsheet from there. You can enter any gear combination, tire size and your speed on the roadway and it will tell you the RPM of your engine for any gear. It was written with the Bonneville in mind and so the ratios and tire sizes that are there when you first open it up are for a stock 2005 Bonneville T100. But all of the values can be changed to match your bike.

I just read your intent to avoid lugging the engine. That's really good to keep that in mind but I rather think you will get a feel for how the engine likes what RPM you are running it rather than trying to calculate and then be thinking about what gear you are in for a given speed while on the road. If anything get a good feel for things and err towards higher RPMs.. These engines work much better at a bit higher RPMs... but you don;t have to go crazy in that direction either..

Good luck
 

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Discussion Starter · #4 ·
I have just gotten my 07 Bonnevile and love it. I wish it had a tach,
but since it doesn't I wish someone could relate gear usage to mph ranges. I would with more usage develop that feel for the appropriate gear --- but in the mean time I want to avoid "lugging down" or "over revving". Your help would be appreciated.
thanks guys --- I had not seen the Tech files you sent me to.
 

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Don't fear winding these things out - redline is high. While I had an 18 tooth front sprocket, it sounded to my ear at least 20 mph for second, 30 for third, 40 for fourth, 50 for fifth. '07's have an 18 tooth as a stock set up.
I've got a 19 tooth now and it's pretty much the same but I tend to wind out the gears a bit more.
 

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Don't fear winding these things out - redline is high. While I had an 18 tooth front sprocket, it sounded to my ear at least 20 mph for second, 30 for third, 40 for fourth, 50 for fifth. '07's have an 18 tooth as a stock set up.
I've got a 19 tooth now and it's pretty much the same but I tend to wind out the gears a bit more.
Not to disagree w/ you David...
I got an 18 Tooth...(up from a stock 17)
I commute daily and w/o a tach I never shift that soon!
10+mph later at least!
I rarely shift into fifth until 65! When riding week ends I drop her from fifth into fourth at 65, wind the hell out of her, and 85 she slips right into fifth!
How many people look or refer to a tach when shifting anyway?
It's all in the ears and feel.
I like to have the throttle response right when and where I need it.
Stock pipes and carbs w/ air boxes have a tendancy to have riders lug instead of using the power band they have...
 

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How many people look or refer to a tach when shifting anyway?
It's all in the ears and feel.
True! Those mph's were meant to be at the bottom of the range - where you will not "lug" the motor. Yeah, generally I am moving faster than that if my front is rather open.
Know what you mean about the tach, but some guys love 'em. When I had a T100, I would look at the tach more out of curiosity than anything else. Now all I have is a mini speedometer!
 

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Revs

Not to worry! You have a rev limiter! If all is open as you like, then you will soon get the feel of when the best time to shift is. I rarely hit the limiter any more since I can feel when the best time to shift is. I am still on the 17 tooth sprocket & thats where I will keep it! I like the xtra ummph!! A tach is nice to look at but no longer a necessity in my book. The motor tells me when to shift! I can break the ton anytime whick I find unecessary. She loves to cruise @ 70-80 & thats what the bike is comfy with. The engine is near bullet proof as well & loves to wind up @ times!!
 

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I wouldn't worry about rpm's as mentioned there is a rev limiter which will let you know when you need to shift.

I never use my tach on any of my bikes, and it is refreshing not to have one on my Bonnie...:D
 

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I have a tach on my T-100. To be honest, I couldn't tell you exactly when I shift even by RPMs...its all sound and feel and what type of riding you're doing.
 

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I would have to agree with Davidc...I shift by sound but when I do have a glance it seems like I'm usually shifting on the 10's..... 20 for second, 30 for third, 40 for fourth...
however, I dont usually hit 5th until I'm at least at highway speed 55-65 or so...
 

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Tach

I find that I only use the tach to verify that "yep that is 5th" when I am wanting to shift to 6th. When I am having fun and running it through it's paces I just go by the sound. I have a 17 tooth and am probably going to go up to a 19 when it is time to replace the chain. I think it would fit my riding a little better. I like the lower gearing when I am riding twisty back roads but not so much running stop light to stop light or hitting the super slab. The bike has enough torque that the lower rpms should not be a problem.

Pops
 
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