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Help me understand my Boxer


pdes

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My R1200RT is a couple of months old and has completed 1200 miles. I am starting to notice certain characteristics of the engine and gearbox and would welcome the comments of seasoned Boxer owners as to whether these characteristics are "the norm". Having moved to the Beemer from a 1200 Suzuki is a massive transition so I a trying not to draw comparisons.

 

Firstly, the engine: I have religiously run in the engine for 600 miles and have begun to "open her up" for the past 600. At around 5000 revs, the engine note changes to a much harsher tone and vibration increases considerably. I have read that this engine is known to smooth-out as it gets older but can I expect a really noticeable improvement?

 

Secondly, the gearbox/transmission: When at low speed, in 1st or 2nd gear, I often hear a "clonk" from the transmission (could be gearbox or driveshaft) when throttling of or at the point of applying power. Also, when changing down into 2nd or 1st, there is a loud clonk as the gears engage.

 

I had expected that, being a BWM, all of the mechanics would be silky smooth but I guess that if these characteristics are the norm, then it's just a case of getting used to them. Despite these observations, I adore the bike.

 

Comments/reassurances gratefully received!

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The boxer engine matures with miles. My '04 R1150RT is smoother now at 52K miles than it was at 2K miles. Vibration on the boxer is heavily impacted by throttle body and valve adjustment balance. The dealer tech will get it in spec. An owner can afford to spend the extra half-hour or so and get it spot on, which makes the engine smoother.

The bike comes 'on-cam' at higher RPM, hence the change in note and feel. This will smooth out with age.

 

The clonking on throttle transition is because of designed-in play in the drive train. As you get used to the bike, and as the engine mellows with age, this will reduce. BMW bike gearboxes are notoriously clonky. Noisy but not a problem.

 

Andy

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An owner can afford to spend the extra half-hour or so and get it spot on, which makes the engine smoother.
Thanks for the reassurance. Any idea where I can get the "DIY" instructions to further tune the mechanics?
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My R1200RT is a couple of months old...Secondly, the gearbox/transmission: When at low speed, in 1st or 2nd gear, I often hear a "clonk" from the transmission...

 

I had expected that, being a BWM, all of the mechanics would be silky smooth but I guess that if these characteristics are the norm, then it's just a case of getting used to them. Despite these observations, I adore the bike.

 

Comments/reassurances gratefully received!

 

Haa Haa lmao.gif

BMW motorcycle transmission silky smooth.. I think not. naver has been, hopefull one day will be!

I am afraid TADT, but the bikes are so adictive you will see past the warts, and love the child as only a mother can! clap.gif

Enjoy

Andy

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An owner can afford to spend the extra half-hour or so and get it spot on, which makes the engine smoother.
Thanks for the reassurance. Any idea where I can get the "DIY" instructions to further tune the mechanics?

 

Most of the data in The OIlhead Maintenance Manual is good for the hexheads. Check on the valve clearance figures - I do not know if they are the same - and omit the 0=0 and idle Throttle sync as they do not apply to your bike. Just do the off-idle sync.

 

Andy

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I actually DO think the BMW transmission is fairly smooth, considering some of the other bikes I've owned, so I have no real gripe with the transmission. The only real negative is the tall first gear and the wide gear spacing, although I understand that it's probably necessary to achieve an appropriate sixth gear ratio given the engine characteristics. Unlike the typical V-twin engine, this thing doesn't run out of juice when you hit 100 mph.

 

But I can ditto the comments on the engine. It seems to really like 3,000 to 4,000 but it starts protesting a bit when you get above that at full throttle. Which is fine, I can get used to it.

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But I can ditto the comments on the engine. It seems to really like 3,000 to 4,000 but it starts protesting a bit when you get above that at full throttle. Which is fine, I can get used to it.

 

Interesting the different viewpoints. To me it feels like the engine really "Kicks In" at 4000 rpm. It's like a whole different engine in the 4-7 range. Which I love...

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Let me clarify what I meant - I agree it starts to kick in above 5,000 in terms of power, but there is a lot of additional vibration. Most engines get smoother the higher you rev them, this one seems to have specific smooth bands. I guess that's to be expected from this type of engine.

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CoarsegoldKid

It'll all get better with age. Vibration on the throttle hand will subside, mine did after the first valve adjustment. But it was never bad, just noticeable. Engine noise, yeah there's a lot of commotion going on down there. Transmission conked a few times at first, now smooth as glass. Give it a few thou more, maybe even 10K. I like mine. You will too. But an in-line four cylinder of 1200cc it ain't. Still a wonderful machine.

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Yes, the engine definitely has more vibes - a bit too much for my sensibilities - above 5K rpm, but the power is there to help me feel better about it. I believe this is typical for this engine.

 

The transmission can be a little clunky getting it into 1st gear, but otherwise I have found it to be quite smooth, with the possible exception of the 1-2 shift which engages better if you rev the engine a bit higher before making that shift.

 

I have found that experience and practice help a lot with the transmission smoothness issue. Experiment a bit, and don't pull the clutch all the way in between shifts. A quick fractional squeeze is all it takes. Some have found that preloading the shift lever helps too.

 

Enjoy!

 

Jay

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... I agree it starts to kick in above 5,000 in terms of power, but there is a lot of additional vibration. ...

Vibration perception depends on whether you are spinning it up slowly on part throttle frown.gif or hitting full throttle whilst wiating patiently for the revs to build to RED before doing it again smile.gif

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As mentioned in an earlier post - throttle body balance makes a world of difference. Also, my bike doesn't mind hard acceleration to the redline nearly as much as cruising at high RPMs in a lower gear. Besides, vibration is really a matter of perception. Find someone to loan you an R1100 oilhead for a few hundred miles. You'll be amazed how smooth the R1200 feels after that.

 

Regarding RT transmissions, they're known more for durability than smoothness. However, much of the clunkiness goes away with time and practice. Learning to preload the shift lever and relieve clutch pressure without completely disengaging the clutch during shifts helps the RT transmission shift much smoother. There was a good post about that a few weeks ago.

 

You've got a great bike. Enjoy the ride!

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I have now put 5000 miles on my new (to me) Boxer twin - my first.

 

Nearly everything you said, I said too: My First Day with R1200ST

 

The bike had 900 miles and its first service done when I got it. Now at 6000 I can say the following:

 

1. Vibration over 4k rpm is almost halved

2. Fuel economy is 10-15% higher

3. It is very clear that the balance of the motor was designed to reduce vibration at legal interstate speeds (65-80mph) where in 6th gear the bike is absolutely smooth

4. Driveline and transmission sounds never go away. It's part of the "character" of the bike.

 

 

Hope this helps, and yes, I *love* my bike!

 

JT

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