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Old 04-02-2013, 09:17 AM   #7906
Gompie
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Originally Posted by MaxReving View Post
You are either joking or ignoring the facts. Take a look at the two pictures below. Red line starts at 9.000 rpm
I'm not sure what we're discussing here. Sure, on straight line acceleration there is an optimal point to shift. That point is when the next gear delivers more torque at that rpm than the gear you're in. And no that is not simply peak power, or peak torque points on the published maps. It's in between, and you'll need to do some extensive excel homework to find out. The shift point changes only by a few 100 rpm across gears, but the good news is feel tells you even better.

The other side is driving style related twisties. This is where you ideally want to drive in one gear, thus not having to downshift for the next turn and keep the bike more balanced. I go 8000+rpm here on my 2010 GS. This is where you offset high rpm, vs one upshift, and one down downshift, on a short distance
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Old 04-02-2013, 09:22 AM   #7907
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Originally Posted by cug View Post
...
What I say is not a BMW thing.
My post was mostly generic.

Now if BMW and GS specifically has "wrong" suspension, is another discussion (I refuse the term "bad" when they always used pretty good OEM as suppliers - it's not that they make the thing themselves).
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Old 04-02-2013, 10:09 AM   #7908
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You don't take it over 9K as the revlimiter kicks in at around 8,900 R's . some engines pull strongly to the rev limiter. When playing Ricky racer in the mountains I often hit the rev limiter with my R1200ST, my R1200S, my R1200GS Cam head and my K1600GT, some bikes, you never do as the power falls decidedly quickly before the rev limiter.
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Old 04-02-2013, 10:17 AM   #7909
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Originally Posted by Deans BMW View Post
You don't take it over 9K as the revlimiter kicks in at around 8,900 R's . some engines pull strongly to the rev limiter. When playing Ricky racer in the mountains I often hit the rev limiter with my R1200ST, my R1200S, my R1200GS Cam head and my K1600GT, some bikes, you never do as the power falls decidedly quickly before the rev limiter.
Actually R1200GS 2004 had it around 7500, 2008 around 8000 and latest oilhead around 8500 (as you know better than me ). My 07 hits rev-limiter (in 6th) fairly easily given enough space.

I wish (all) GS had longer 6th though.
(or is time to see 7th on consumer bikes - overdrive for bikes like GS and normal on sport bikes)
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Old 04-02-2013, 11:01 AM   #7910
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Originally Posted by kindofblue View Post
Nice looking Trek. And a hard tail at that. How much does it weigh?
I think it is around 12 kg (25 lbs). In my region a hard tail is logic, sand and farmlands and forest is on offer and it is almost all flat. For mountainbikes there are nice tracks.
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Old 04-02-2013, 11:52 AM   #7911
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Originally Posted by IB1 View Post
I've been riding for most of the weekend. But not on my GS

Judging from the bottles on the ground, looks like you've been doing a little as well Perhaps to celebrate your new bike! I'm a mountain biker as well....pedal on Saturdays, ride on Sundays!
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Old 04-02-2013, 12:04 PM   #7912
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Originally Posted by MaxReving View Post
Totally agree. Don't look at the rev range, look at the road. Engine will automatically cut out when you get into the red rev zone.

Max :-)
But I like to ride down the road staring at my instruments the whole time and completely ignoring the road The GPS blocking the top portion of the tach for us taller riders is just poor design...
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Old 04-02-2013, 12:09 PM   #7913
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Originally Posted by MaxReving View Post
You are either joking or ignoring the facts. Take a look at the two pictures below. Red line starts at 9.000 rpm and then compare it with the power and torque figures in the other picture (R1200GS LC is the light blue lines).

125 hp @ 7.700 rpm
125 Nm @ 6.500 rpm

What makes it more fun to take the engine over 9.000 rpm ? (in that range it has lost power and torque !! )

Max :-)

Quote:
Originally Posted by Gompie View Post
I'm not sure what we're discussing here. Sure, on straight line acceleration there is an optimal point to shift. That point is when the next gear delivers more torque at that rpm than the gear you're in. (I agree) And no that is not simply peak power, or peak torque points on the published maps. It's in between, and you'll need to do some extensive excel homework to find out. (it is quite easy) The shift point changes only by a few 100 rpm across gears, but the good news is feel tells you even better.

The other side is driving style related twisties. This is where you ideally want to drive in one gear, thus not having to downshift for the next turn and keep the bike more balanced. (I agree) I go 8000+rpm here on my 2010 GS. This is where you offset high rpm, vs one upshift, and one down downshift, on a short distance
My argument was just that you won't get the maximal power, torque and acceleration if you rev it into the redline range. Not in any gear. Here are the rules:

Engine horse power = Engine torque x Engine rpm
Engine torque = Engine horse power / Engine rpm
Wheel torque = Engine torque x Transmission Gearing

Since torque is equal to acceleration then the maximum acceleration is reached at maximum Wheel torque. In this case in first gear at 6.500 rpm

Taking into consideration that the gearing on the new 1200GS LC looks like this:

1. gear = 2.438
2. gear = 1.714
3. gear = 1.296
4. gear = 1.059
5. gear = 0.943
6. gear = 0.848

Ratio between the gear are:

1. to 2. gear = 0.703
2. to 3. gear = 0.755
3. to 4. gear = 0.817
4. to 5. gear = 0.892
5. to 6. gear = 0.899

If you look at the torque graph above then you can see that you will have the maximal acceleration available in these rev ranges:

1. gear (1.000 ... 7.500 rpm) (000 ... 117 Nm) (000 ... 071 kmh)
2. gear (5.280 ... 7.300 rpm) (118 ... 119 Nm) (071 ... 097 kmh)
3. gear (5.510 ... 7.300 rpm) (119 ... 119 Nm) (097 ... 129 kmh)
4. gear (5.960 ... 7.000 rpm) (120 ... 123 nm) (129 ... 152 kmh)
5. gear (6.250 ... 7.000 rpm) (123 ... 123 Nm) (152 ... 170 kmh)
6. gear (6.300 ... 6.500 rpm) (124 ... 125 Nm) (170 ... 176 kmh)

Speed @ max. power: (7.700 rpm) = 209 kmh

(Edit: speed added and edited)

Figures in the first () are revs and figures in second () are torque.

What does this mean? I means that if you rev you bike past the figures listed above in red then you are going to lose the race around the race track or to the top of the mountain pass. It is true that you for the benefit of balancing your bike can take advantage of less gear shifting but if the other guy behind you are better at gear shifting then he will pass by you a some point. Redlining your engine may be fun but it is not going to make you faster unless you are hopeless at gear shifting. Again my point was just that you won't get the maximal acceleration if you rev into the redline range at 9.000 rpm.

Max :-)

MaxReving screwed with this post 04-03-2013 at 05:02 AM
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Old 04-02-2013, 12:11 PM   #7914
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Nooooo you have it all wrong. The BMW design is perfect in every way, it's the taller people that are the poor design
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Old 04-02-2013, 12:47 PM   #7915
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Nooooo you have it all wrong. The BMW design is perfect in every way, it's the taller people that are the poor design
Haha
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Old 04-02-2013, 01:00 PM   #7916
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Originally Posted by Marki_GSA View Post
Nooooo you have it all wrong. The BMW design is perfect in every way, it's the taller people that are the poor design
I have to agree, it works perfectly for me.
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Old 04-02-2013, 01:16 PM   #7917
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I bought a 2012 Rallye and love it. When the new one came out, I thought about for a while, and decided to stay with the 2012. I am going to South America for 2 months this fall, and wanted the reliability and parts availability of the old model. But if you will be doing short trips in North America or Europe, I would buy the 2013.
The bike is faster, handles better, has a ton more worthwhile features. The only thing I don't like is that most of the stuff I bought for my 2012 will not fit on the new bike. But that is part of the BMW mktg plan, isn't it.

I was just at Rawhyde Adventure School and loved it. Spent a few days with one of the guys that went to the BMW launch in S Africa. Much of my thoughts came from his experiences. I will likely buy a new Adventure when it comes out.
Very good point Scottishman
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Old 04-02-2013, 01:19 PM   #7918
Deans BMW
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Maxreving, I agree with your thinking, BTW that graph is for the Oilhead GS, the Cam head runs around 98-100 RWHP and the curve is a little flatter towards the revlimiter, some engines will hardly hit the revlimiter, both my 2010 Camhead R12GS and my R1200S oilhead hit it quiet easily. The R1200S and my R1200ST hit it easily in 6th gear.
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Old 04-02-2013, 01:29 PM   #7919
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Originally Posted by EJ_92606 View Post
But I like to ride down the road staring at my instruments the whole time and completely ignoring the road The GPS blocking the top portion of the tach for us taller riders is just poor design...
Man, it is just a bracket that is a bit low.

I mean come on...

Quote:
Originally Posted by Marki_GSA View Post
Nooooo you have it all wrong. The BMW design is perfect in every way, it's the taller people that are the poor design
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Old 04-02-2013, 01:36 PM   #7920
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But I like to ride down the road staring at my instruments the whole time and completely ignoring the road The GPS blocking the top portion of the tach for us taller riders is just poor design...
I saw my dealer adjusting one today. Took less than 5 min:)

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