Questions on the 12GS versus the 12RT

[mistercindy]

I have an '05 12GS and am considering trading it in on an '07 or '08 12RT (the K12GT is tantalizing, but I just don't think I need to go there!). I'm just considering a change and I'm pondering the RT. Offhand I like the larger RT fuel tank and the fact that the servos will be gone. The biggest chunk of my riding is a 60 mile round trip commute to work (when I can) on urban highways. But I do a number 300-600 mile day and/or weekend trips over the course of a year, too. I average around 12,000 miles per year 99% of which is on paved roads. I did test ride the 12RT once for a few miles when I was tired of the buffeting on the 12GS (which I cured with an Aeroflow). My biggest memory of the 12RT was that the mirrors were in an odd place, but I sense that is something one just gets used to.

Anyway, for those of you that have owned or extensively ridden the two, what do you find to be the main differences in the ride? What are your preferences? Did you find the 12RT to be buzzier than the 12GS (another thing I've read)? Etc...?

I've also got some questions involving the specs (from the BMW web site) that I'm hoping some of you may be able to answer. Forgive me, but other than the simplist things like changing fluids, bulbs, etc..., I've never made myself become much of a wrench.

- The "Primary Drive" is a different on the two bikes. What does that mean?

- The "Front Travel" and "Rear Travel" are different, too, with the GS's being several inches longer than the RT's. What does that mean?

- I had read somewhere that the gear ratios were different (ie., lower RPM's for the RT at highway speeds), but the specs I see at the BMW website say they are identical. Did that change, or did I read wrong?

Thanks for taking the time.

[The_Veg]

Hi Grant,
I can't answer your technical questions, but have you compared the ergos of the RT to your GS? If you need legroom, the GS is the way to go.

[kbasa]

Ah, well. I've got both in the garage.

If you want to eat large quantities of miles in complete comfort, it's hard to beat the RT. When they're talking about travel, they're talking about suspension travel. The GS, because of it's intended use, gets more. That doesn't mean the RT is less comfy, it's just not got as much travel.

The final drives are different, with different ratios in them.

I can sum it up this way:

If you're going to carry you and your junk and expect to find some dirt stuff to ride on, take the GS. If you need to dispose of lots of miles, take the RT.

If you want to hoon around the backroads and tear it up, either will do the job, but the RT is more work than the GS, primarily because of the weight difference and the width and leverage of the bars.

One RT tip: Get a CalSci windshield. They're odd looking, but the bike is much quieter now.

You live in DFW, right? The RT will be much warmer in hot weather than the GS, that's a dead certainty.

[SNC1923]

I can't answer your question directly, but I can obliquely.

I had an 1150 RT and now have a 1200 GSA.

Both are excellent touring bikes. The 1200GSA handles infinitely better and is much, much more comfortable. I know that's counterintuitive, but it's true nonetheless.

As Dave indicated above, my RT got warm during the Bakersfield summers (read: Hell).

If I could have both, I would. My wife prefers the RT. But the GS handles like a Schwinn by comparsion. I understand the 12RTs are a better design (more up-to-date) than the 1150, of course, so it's not an entirely fair comparison.

The GS is a better all-around bike and has better luggage capacity to boot.

That's my 0.02, just about what it's worth.

[BradfordBenn]

I have done the RT for long miles but only done a F650GS not a R series. I can tell you that the RT is much easier to do long miles for many days in a row. You will probably have fun on either one you get.

[meisco]

The R1100RT is an all-around, good, reliable, fun, great-handling bike.

The R1200GS is a kick-in-pants, hoot-out loud, grin on your face for days kind of bike.

The GS is harder to manuever than the RT in slow traffic and at stops (I'm short). I do feel safer (more in control) in real slow traffic on the RT.

The GS has my vote. More luggage options. Better handling at speed. and you just have to love that WOW factor.

[sfdave]

I thought I would want a new RT to replace my wrecked 1150GS. I rode both the RT and the GS, loved the cruise control on the RT. Thought it a bit heavy and it rattled a bit on the rough stuff.

Well, of course I bought a R1200GS because, as stated, the WOW factor is there. It feels like an extension of my hands! You can throw it around all day without wearing you out, and I really love it for Calif lane splitting! Plus you can still eat up many miles a day.

But if I could have both...

[kbasa]

I thought I would want a new RT to replace my wrecked 1150GS. I rode both the RT and the GS, loved the cruise control on the RT. Thought it a bit heavy and it rattled a bit on the rough stuff.

Well, of course I bought a R1200GS because, as stated, the WOW factor is there. It feels like an extension of my hands! You can throw it around all day without wearing you out, and I really love it for Calif lane splitting! Plus you can still eat up many miles a day.

But if I could have both...


When am I gonna see this thing?

[dancogan]

Just a note about the comments on how hot the 1200RT might be: I think they're referring to the fact that it's a fully faired bike. thus, between the electrically adjustable windshield and full fairing, you don't get hit with a lot of wind. There's no engine heat to speak of.
If you tour a good bit and like cruise control, the RT may be the way to go. If you tour 2-up, then it may be the only way to go. (Your passenger may vary.)

[henzilla]

[QUOTE=mistercindy;259700]
Anyway, for those of you that have owned or extensively ridden the two, what do you find to be the main differences in the ride? What are your preferences? Did you find the 12RT to be buzzier than the 12GS (another thing I've read)? Etc...?QUOTE]

I have '05 models of both, the GS the latest. I like both, don't really miss the HP difference due to the weight difference from the RT to the GS, unless I am trying to keep up with other RT's, then I just wind it up a little more.There is a gearing ratio difference I notice going back and forth . The GS is a better all around do it all bike in my mind. I like the protection of the RT in rain and cold, but the GS is fine with good gear. Miss the cruise control, push button windshield tweaking ,the data computer and the 7 gallon tank when on the GS, but it sure is lighter when stuck in traffic. I do not notice the heat as much on the RT with fairing, the GS heat rolls up my leg in traffic. And as mentioned ...WOW is a constant when on the GS, the forks/suspension are different, the RT seems to snap sharper in tight turning,but the GS is very close. My biggest feel differnce is hand/arm position. The GS wide and up, the RT close and low ,which feels more pronounced going from GS to RT. The GS seemed buzzier thru the bars , but it is a big twin and I like it!

Boy, that was long winded...

[cjack]

I have an '05 12GS and am considering trading it in on an '07 or '08 12RT (the K12GT is tantalizing, but I just don't think I need to go there!). I'm just considering a change and I'm pondering the RT. Offhand I like the larger RT fuel tank and the fact that the servos will be gone. .

Actually, there is still a pump motor for the integral operation of the rear brake when the front brake and rear brake are applied with the hand lever alone. When the foot brake lever is pressed, at some point it overcomes the pressure from the pump motor and the operation of the rear brake is determined by the foot brake lever alone.
I don't see an issue with either system.
Most folks that get a GS after having a gaggle of other models, stick with the GS around here. I'm afraid to ride one.

[soffiler]

I have an '05 12GS and am considering trading it in on an '07 or '08 12RT...

Anyway, for those of you that have owned or extensively ridden the two, what do you find to be the main differences in the ride? What are your preferences? Did you find the 12RT to be buzzier than the 12GS (another thing I've read)? Etc...?

I own an '05GS and I have done a fair number of miles on my buddy's '06 RT. What I notice instantly when I hop on the RT is low-speed stability. The RT always makes me feel I could plop my feet on the pegs and just sit there stationary without tipping over. At speed, there are definite differences in the steering geometry. The first couple times I bank the RT into a corner, my lines are a bit messy as my brain re-calibrates to the RT's combination of handling characteristics and feedback from the bars. There is nothing wrong with the RT, it's just different. I am able to make the adjustment in a few minutes and then the RT feels just as natural as can be.

I do not think the RT is buzzier than the GS, nope. In fact, from the footpeg level, the RT is significantly less buzzy. (Disclaimer: I run my GS with the footpeg rubbers removed). From the bars, it's about a wash.

-The "Primary Drive" is a different on the two bikes. What does that mean?

The primary drive is the first gear reduction, between the crankshaft and the flywheel.

-The "Front Travel" and "Rear Travel" are different, too, with the GS's being several inches longer than the RT's. What does that mean?

Travel is suspension travel, the total amount that the wheel can move up and down. The rough-road/dirt-road (I will quit just short of "off-road") nature of the GS suspension demands a longer travel, which provides greater ground clearance and the ability to soak up larger imperfections.

- I had read somewhere that the gear ratios were different (ie., lower RPM's for the RT at highway speeds), but the specs I see at the BMW website say they are identical. Did that change, or did I read wrong?

Um, with all due respect, you are reading it wrong. What you are seeing is the TRANSMISSION ratio's, which indeed are identical. But you are failing to factor in the effects of the primary drive and the final drive, both of which are different.

Anyone who spends any time at all observing their speedometer and tachometer comes to understand they are related. In fact, one can calculate the exact relationship between engine rpm and vehicle speed. You need to know:

- primary drive ratio
- transmission ratio (there are six different ones, of course!)
- final drive ratio
- rear tire effective diameter

and from that you can calculate that exact relationship between engine rpm and vehicle speed.

[sfdave]

When am I gonna see this thing?

Soon...not this Sat. because her big yellow shocks are being installed :D

[henzilla]

.
Most folks that get a GS after having a gaggle of other models, stick with the GS around here. I'm afraid to ride one.

Kinda what's happening to me! :laugh then I rode a dang K 1200 S

[kbasa]

The primary drive is the first gear reduction, between the crankshaft and the flywheel.





Uh, the flywheel bolts directly to the end of the crankshaft. The input spline from the trans plugs directly into the end of the crankshaft and has the clutch riding on it. It works just like every BMW boxer that preceded it.

[soffiler]

Uh, the flywheel bolts directly to the end of the crankshaft. The input spline from the trans plugs directly into the end of the crankshaft and has the clutch riding on it. It works just like every BMW boxer that preceded it.

errr... whoops... am I picturing a K engine then? Moot point regardless.

Primary reduction handled inside the transmission?

[mistercindy]

Thank you very much for the responses.:thumb

I went to the dealer yesterday evening and will test ride both the 12RT and the K12GT on Saturday. I'm also going to see if I can rent a 12RT somewhere in the Dallas area. If I can rent it for a weekend day I can really put it through some paces and get a better feel for it than I'll get in a 10 or 20 miles test ride.

Some thoughts based on your comments:

Hi Grant,
I can't answer your technical questions, but have you compared the ergos of the RT to your GS? If you need legroom, the GS is the way to go.I don't think leg room will be an issue. A short sit on the 12RT seems pretty comfy.




You live in DFW, right? The RT will be much warmer in hot weather than the GS, that's a dead certainty.It is hot here in DFW during the summer and that is a consideration. But lots of folks warned I'd really feel it with the Aeroflow on my 12GS, but that hasn't been the case. With the 12GS Aeroflow I actually get a fair amount of clean air on my chest and arms. The hope is that I wouldn't lose that with a 12RT.




Well, of course I bought a R1200GS because, as stated, the WOW factor is there....and you just have to love that WOW factor.There is certainly a WOW factor with the 12GS. Of all the bikes I've owned, only one has caused people to follow me in order to ask questions about it!:D One guy followed me in his car flicking his brights, trying to get my attention, etc... I thought he was nuts. At the next red light he asked if I'd pull over so he could ask about the bike! Another time I had pulled my bike into my garage, put my gear up, and a guy comes sprinting breathlessly up my driveway. He'd followed me home (in a late model M3, by the way) to talk about the bike!:D




Anyone who spends any time at all observing their speedometer and tachometer comes to understand they are related. In fact, one can calculate the exact relationship between engine rpm and vehicle speed. You need to know:

- primary drive ratio
- transmission ratio (there are six different ones, of course!)
- final drive ratio
- rear tire effective diameter

and from that you can calculate that exact relationship between engine rpm and vehicle speed.So, do I understand correctly that the RPMs with various speeds will be different from the 12GS to the 12RT because the primary and final drive ratios are different even though the transmission ratios are identical? On my 12GS's sixth gear, 4,000 RPM's gets me 72 MPH. I'm guessing that on the 12RT the speed will be a bit higher for 4,000 RPM's because of the primary and final drive ratios?

[soffiler]

So, do I understand correctly that the RPMs with various speeds will be different from the 12GS to the 12RT because the primary and final drive ratios are different even though the transmission ratios are identical?

Correct!


On my 12GS's sixth gear, 4,000 RPM's gets me 72 MPH. I'm guessing that on the 12RT the speed will be a bit higher for 4,000 RPM's because of the primary and final drive ratios?

Correct. I actually did that math a while ago. Working from memory (which already failed me once today, thanks Dave) the RT was around 75 or 76mph at 4000rpm in sixth.

[The_Veg]

There is certainly a WOW factor with the 12GS. Of all the bikes I've owned, only one has caused people to follow me in order to ask questions about it! One guy followed me in his car flicking his brights, trying to get my attention, etc... I thought he was nuts. At the next red light he asked if I'd pull over so he could ask about the bike! Another time I had pulled my bike into my garage, put my gear up, and a guy comes sprinting breathlessly up my driveway. He'd followed me home (in a late model M3, by the way) to talk about the bike!

I've had two cagers ask or comment about the GS while stopped at lights. Both really liked it, and both, oddly, were on 121 in The Colony.

[mistercindy]

I've had two cagers ask or comment about the GS while stopped at lights. Both really liked it, and both, oddly, were on 121 in The Colony.How funny! Both of mine were just north of the 121 and Hwy 75 intersection in McKinney!




Correct. I actually did that math a while ago. Working from memory (which already failed me once today, thanks Dave) the RT was around 75 or 76mph at 4000rpm in sixth.Thank you sir! That's the kind of info I was looking for. So the 12RT is nothing like that tall passing 6th gear of the 1150 engines, which if memory serves from my R1150R days, was 80 MPH at 4,000 RPM's. But its closer to it than the 12GS.

[Bfish]

I've had two cagers ask or comment about the GS while stopped at lights. Both really liked it, and both, oddly, were on 121 in The Colony.

can top that. had a gentleman in a beat up 'ol pick em up truck stop next to me (was on the RT) at a red light somewhere in Georgia a couple of years ago. only question he had, and it was clear as day, was "how much did that cost?". the nerve.:D

my answer...."less than a harley":clap

apologize for the hijack.

[soffiler]

Perhaps my most interesting GS encounter was with a police officer in the Michigan UP (I believe we were rolling in to Iron Mountain, MI). It was dark, the town was unfamiliar, and I was riding very carefully, travelling at precisely the speed limit. The officer, driving an official pickup truck (hey, it's the UP) pulled a U-turn and followed me into a gas station. I was wondering what I'd done when the young officer jumped out and approached me enthusiastically. Turns out he had his sights set on a GS and wanted to know all about it.

[kbasa]

How funny! Both of mine were just north of the 121 and Hwy 75 intersection in McKinney!




Thank you sir! That's the kind of info I was looking for. So the 12RT is nothing like that tall passing 6th gear of the 1150 engines, which if memory serves from my R1150R days, was 80 MPH at 4,000 RPM's. But its closer to it than the 12GS.

You'll find that the party zone of the powerband on the 12s starts a bit higher up than it did on the 1150s. I think peak torque on the R12RT and GS is right about 5500 or so, which about 1K higher than on the older oilheads. Of course, redline is higher as well, so it's not really a problem. I think peak power is at about 7500rpms?

In any case, the gearing seems to work pretty well with the powerbands in either bike.

[cjack]

can top that. had a gentleman in a beat up 'ol pick em up truck stop next to me (was on the RT) at a red light somewhere in Georgia a couple of years ago. only question he had, and it was clear as day, was "how much did that cost?". the nerve.:D

my answer...."less than a harley":clap

apologize for the hijack.

I used to say about the same as a used vehicle instead of having a second car.

[soffiler]

You'll find that the party zone of the powerband on the 12s starts a bit higher up than it did on the 1150s. I think peak torque on the R12RT and GS is right about 5500 or so, which about 1K higher than on the older oilheads. Of course, redline is higher as well, so it's not really a problem. I think peak power is at about 7500rpms?

In any case, the gearing seems to work pretty well with the powerbands in either bike.

Agreed, Dave. Party zone is a bit higher up, and it hits noticably harder than the 1150 when it hits. According to HP and T charts for '05 GS found on www.r1200gs.info, from the offical BMW press release, T peak is indeed at 5500rpm. HP peak appears to be at about 7200rpm.

My buddy's '06 RT appears to have a different cam (or something). His claimed HP is a bit higher (not going to quote numbers from my faulty memory) and his redline is about 500rpm higher as well. Versus my '05 GS, that is.

[Professor]

Hey MisterCindy,

I just bought my first BMW (a new '07 R1200RT) two weeks ago and am wanting to meet other area Beemer riders. I live in Garland and work in N. Dallas. Maybe we can meet sometime.

The RT is in the shop tonight for it's first service and installation of some goodies so I'll be riding my Moto Guzzi Jackal to work tomorrow. It will be interesting to see how the Jackal feels after two weeks of the RT.

[The_Veg]

Professor, come to Humperdink's at 75 and Campbell in Richardson on the 19th around 7 PM and you can meet a whole roomful of Dallas-area Beemerphiles.
It'll be the monthly meeting of the Lone Star BMW Riders. I'm the tall goofy redheaded guy with the black GS. :wave


Ben Lower
VeeP,
Lone Star BMW Riders

[Professor]

Thanks, Ben. I'll try to be there. I'll be the blond guy in his 60's (actually I must be in someone else's 60's - it can't be mine) and a Hi-Viz yellow jacket.

I had this buyer's remorse related fear that riding my Jackal yesterday - the first time in two weeks - would be as much or more fun than the new RT. Not to worry. The Moto Guzzi is a good bike, but the RT is so much more. It felt good to have the Beemer back.

[mistercindy]

Professor, come to Humperdink's at 75 and Campbell in Richardson on the 19th around 7 PM and you can meet a whole roomful of Dallas-area Beemerphiles.
It'll be the monthly meeting of the Lone Star BMW Riders. I'm the tall goofy redheaded guy with the black GS. :wave


Ben Lower
VeeP,
Lone Star BMW RidersI've heard about that meeting. I believe a buddy of mine once gave a slide show of his Dallas to Tierra del Fuego trip at one of those meetings. I gotta make that some day. Thanks for the reminder.

[The_Veg]

I believe a buddy of mine once gave a slide show of his Dallas to Tierra del Fuego trip at one of those meetings.

Are you talking about Bo Griffin? He's the club's TourMeister.

[mistercindy]

Are you talking about Bo Griffin? He's the club's TourMeister.Yes, I was speaking of Bo. My wife has known Bo's wife for over 30 years, and I met them 25 years ago when my wife and I started dating. I occasionally attend Bo's Sunday morning rides.

[The_Veg]

I've been on a ride or two of Bo's...I might have even met you without realising I knew you on the forum...I'll keep an eye peeled next time I make a ride.

Do you ever go to the Thursday night thing at the Starbucks in Plano? I sometimes do.

[mistercindy]

Do you ever go to the Thursday night thing at the Starbucks in Plano? I sometimes do.I've never heard of that one. Which Starbucks?

[mistercindy]

Hey MisterCindy,

I just bought my first BMW (a new '07 R1200RT) two weeks ago and am wanting to meet other area Beemer riders. I live in Garland and work in N. Dallas. Maybe we can meet sometime.

The RT is in the shop tonight for it's first service and installation of some goodies so I'll be riding my Moto Guzzi Jackal to work tomorrow. It will be interesting to see how the Jackal feels after two weeks of the RT.
Hey, Professor, it turns out we sat next to each other at dinner this evening! I didn't know for sure until I looked at your profile and saw that Guzzi!

Nice to have met you!

[The_Veg]

Great meeting both of you guys, and I hope to see you again at future meetings as well as out on the road!

Ben Lower
VeeP, Lone Star BMW Riders

[Professor]

You too, Grant and Ben. That's pretty wild. You are the only two I have really talked to on the forum and we end up sitting together.

I was going to join and buy a t-shirt, but when I got up to the front, everyone "official" was busy talking with someone else.

It seems like a group I will enjoy - not the "elitist snobs" I've always heard ride BMW's. You guys and gals are pretty groovy. :dance :)

I look forward to some rides and getting to know everyone better.

Jim

[1analguy]

can top that. had a gentleman in a beat up 'ol pick em up truck stop next to me (was on the RT) at a red light somewhere in Georgia a couple of years ago. only question he had, and it was clear as day, was "how much did that cost?". the nerve.:D

my answer...."less than a harley":clap

apologize for the hijack.

His reply should have been: "You get what you pay for"...;)

[Rob Nye]

Ah, well. I've got both in the garage.

If you want to eat large quantities of miles in complete comfort, it's hard to beat the RT. When they're talking about travel, they're talking about suspension travel. The GS, because of it's intended use, gets more. That doesn't mean the RT is less comfy, it's just not got as much travel.

The final drives are different, with different ratios in them.

I can sum it up this way:

If you're going to carry you and your junk and expect to find some dirt stuff to ride on, take the GS. If you need to dispose of lots of miles, take the RT.

If you want to hoon around the backroads and tear it up, either will do the job, but the RT is more work than the GS, primarily because of the weight difference and the width and leverage of the bars.

One RT tip: Get a CalSci windshield. They're odd looking, but the bike is much quieter now.

You live in DFW, right? The RT will be much warmer in hot weather than the GS, that's a dead certainty.

Ditto on every point.

I would add that you will want to upgarde the RT suspension earlier. If you camp and tour stay with the GS.

Like Dave I have a GS (Adventure) and an RT (P). If I could only keep one it would be the Adventure.

Perhaps this is where you should be looking. The only thing you posted about the RT that is an absolute is the larger tank which you get with the Adventure. Stock screen is fine too.

[Eureka]

I'm another one with both an RT and GS in the garage, both 2005's. Here's my opinon.

For trips the RT excels due to its superior wind/weather protection, cruise control, bigger side bags, heated seat, and adjustable windshield height. I have a CeeBaily windshield and a Rich's saddle.

The GS final drive/differential is geared lower so it accelerates much faster but also is a little buzzy at high speeds, which it is fully capable of. This is a very quick bike that will run out to over 100 mph in an eye blink if you aren't attentive.

The GS is lighter and feels lighter as you ride it, especially in corners and while cornering. The wind noise/buffeting is greater on the GS, even with an Aeroflow windshild. The seating position on the GS gives you a little more leg room if you have a long inseam. I put a Tourtech long distance comfort saddle on the GS.

I've ridden both bikes in rain, and surprisingly, stayed about as dry on the GS as on the RT, once up to speed. You will get more water splashed up on your feet and lower pants legs on the GS.

Final decision: base it on how and where you ride. Also, how well do you tolerate wind buffeting and noise. I ride the RT on any ride where weather may be a factor and on all long trips. I ride the GS on day trips and short rides that may include dirt roads. Good luck!

[The_Veg]

I was going to join and buy a t-shirt, but when I got up to the front, everyone "official" was busy talking with someone else.

No worries Jim! Come to the next one and just butt in if you run into the same problem again. We'll be happy to have you. :)

[mistercindy]

You too, Grant and Ben. That's pretty wild. You are the only two I have really talked to on the forum and we end up sitting together.Yes, that belongs in the "Its a Small World" department.:D