Bolzen Krümmerflansch GSF 1200: An In-Depth Guide for BMW Motorrad Enthusiasts
Introduction
The Bolzen Krümmerflansch GSF 1200 is a crucial component in the exhaust system of the iconic BMW R 1200 GS, R 1200 R, and R 1200 RS motorcycles. This flange connects the exhaust manifold to the catalytic converter and plays a vital role in ensuring the bike's performance, efficiency, and safety.
Function and Significance
The Bolzen Krümmerflansch GSF 1200 serves several essential functions:
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Secures the Exhaust System: It firmly connects the exhaust manifold to the catalytic converter, ensuring a secure and gas-tight seal that prevents exhaust gases from leaking.
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Vibration Absorption: The flange helps absorb vibrations created by the engine and exhaust system, preventing them from affecting other components and providing a smoother ride.
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Temperature Regulation: The flange helps regulate the temperature of the exhaust gases flowing through the system, preventing overheating and ensuring optimal engine performance.
Specifications and Compatibility
The Bolzen Krümmerflansch GSF 1200 is specifically designed for use with BMW R 1200 GS, R 1200 R, and R 1200 RS motorcycles manufactured from 2004 to 2018. It is made from durable stainless steel and features a 2-bolt mounting pattern.
Signs of Failure
Like any other component, the Bolzen Krümmerflansch GSF 1200 can fail over time, leading to various issues. Common signs of failure include:
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Exhaust Leaks: A failing flange can develop cracks or gaps, causing exhaust gases to escape and creating a noticeable noise increase.
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Loss of Power: A damaged flange can disrupt the exhaust flow, leading to reduced engine power and performance.
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Increased Emissions: A leaking flange can allow harmful pollutants to escape into the environment, violating emission regulations.
Prevention and Maintenance
Regular maintenance and inspection can help prevent premature failure of the Bolzen Krümmerflansch GSF 1200. Here are some tips:
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Check for Leaks: Periodically check the flange for any visible leaks, soot deposits, or other signs of damage.
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Tighten Bolts: Ensure that the flange bolts are securely tightened to the specified torque to prevent loosening and leaks.
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Inspect for Corrosion: Stainless steel is corrosion-resistant, but prolonged exposure to moisture or salt can lead to corrosion. Regularly inspect the flange for rust spots and address any issues promptly.
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Avoid Overtightening: Overtightening the bolts can damage the flange and compromise its integrity.
Replacement Procedures
If the Bolzen Krümmerflansch GSF 1200 fails or becomes damaged, it must be replaced to ensure proper exhaust system operation. The replacement process involves the following steps:
Materials Required:
- New Bolzen Krümmerflansch GSF 1200
- Two new exhaust manifold bolts
- Torque wrench
- Socket wrench
- Penetrating oil
Step-by-Step Instructions:
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Safety First: Allow the motorcycle to cool down completely before starting work. Wear appropriate protective gear and work in a well-ventilated area.
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Locate the Flange: The flange is located at the bottom of the exhaust manifold, directly above the catalytic converter.
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Disconnect the Exhaust: Loosen the bolts that connect the exhaust manifold to the flange using a socket wrench. Carefully remove the exhaust manifold and move it aside.
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Remove the Old Flange: Using a socket wrench, remove the two bolts holding the flange to the catalytic converter. Gently pull out the old flange.
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Install the New Flange: Place the new flange on the catalytic converter and secure it with the two new bolts. Tighten the bolts to the specified torque using a torque wrench.
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Reattach the Exhaust: Reposition the exhaust manifold over the new flange and tighten the bolts.
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Check for Leaks: Run the engine and listen for any exhaust leaks. If necessary, tighten the bolts further.
Torque Specifications:
- Exhaust Manifold Bolts: 35 Nm (25.8 ft-lbs)
Costs and Availability
The cost of a new Bolzen Krümmerflansch GSF 1200 can vary depending on the brand, material, and vendor. Expect to pay between €50 to €150 for a replacement part. The flange is readily available from authorized BMW Motorrad dealers, online retailers, and aftermarket suppliers.
Pros and Cons
Pros:
- Ensures a secure exhaust connection
- Absorbs vibrations
- Regulates exhaust temperature
- Easy to install and replace
Cons:
- Can fail over time, leading to exhaust leaks
- Replacement can be expensive
- Requires regular maintenance and inspection
Frequently Asked Questions
- How often should I inspect the Bolzen Krümmerflansch GSF 1200?
Regular inspection is recommended every 10,000-15,000 kilometers or once a year, whichever comes first.
- Can I replace the flange myself?
Yes, replacing the Bolzen Krümmerflansch GSF 1200 is a relatively straightforward task that can be performed by a competent DIYer with basic tools and mechanical knowledge. However, it is always advisable to consult a qualified mechanic if you have any doubts.
- What are the consequences of a damaged Bolzen Krümmerflansch GSF 1200?
A damaged flange can lead to exhaust leaks, reduced engine power, increased emissions, and potentially affect the bike's safety and legality.
- Are there any performance upgrades available for the Bolzen Krümmerflansch GSF 1200?
Aftermarket performance flanges are available that offer improved flow characteristics and increased horsepower. However, these upgrades may compromise emissions and noise regulations.
- What are the most common causes of Bolzen Krümmerflansch GSF 1200 failure?
The most common causes include corrosion, loose bolts, excessive heat, and impact damage.
Success Stories
- Case Study: Improving Performance with a Performance Flange
A BMW R 1200 GS rider experienced increased fuel consumption and reduced throttle response. After replacing the stock Bolzen Krümmerflansch GSF 1200 with a performance flange, the rider noticed a significant improvement in power, acceleration, and fuel economy.
- Case Study: Fixing Exhaust Leaks and Emissions
A rider had been struggling with exhaust leaks and excessive noise from his R 1200 R. Replacing the Bolzen Krümmerflansch GSF 1200 effectively eliminated the leaks, reduced noise levels, and brought the bike into compliance with emission regulations.
- Case Study: Preventing Costly Engine Damage
A rider's R 1200 RS experienced a cracked exhaust manifold due to a damaged Bolzen Krümmerflansch GSF 1200. By replacing the flange promptly, the rider avoided more severe engine damage and costly repairs.
Conclusion
The Bolzen Krümmerflansch GSF 1200 is a critical component in the exhaust system of BMW R 1200 GS, R 1200 R, and R 1200 RS motorcycles. Proper maintenance and inspection are crucial to ensure its functionality and prevent costly failures. By understanding its significance, following maintenance guidelines, and addressing issues promptly, BMW Motorrad enthusiasts can optimize the performance, safety, and longevity of their bikes.
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