BMW K1200, K1300, and K1600 Forum banner
1 - 3 of 3 Posts

·
Registered
2013 K1300R
Joined
·
37 Posts
Discussion Starter · #1 ·
I have been looking at after market mufflers and most of them are 51mm variety (51mm muffler intake). I have a Titanium Oval Delkevic and recently bought a Tri Oval Carbon (450mm long). Both mufflers have a 51mm intake. According to Delkevic Dyno sheet online, the performance increased by a few HP, so I guess the 51mm diameter is enough.

Is 51mm diameter muffler the norm for this bike and is it enough considering the 175 HP ?

I am asking as some 1250cc bikes (like Suzuki Bandit 1250) uses a larger 61mm muffler.
 

·
Registered
K1300GT SE / GSX1400 / LRD4
Joined
·
222 Posts
I think as per other posts on this issue, narrowing from the factory link pipe to the muffler would increase temp and back pressure, possibly limiting hp. Each engine is different, so only a before and after dyno run would tell.

Personally I would be looking for a muffler that doesn't have a restriction at the lower connector, allowing free-flow exhaust. Just my opinion.
 

·
Registered
2013 K1300R
Joined
·
37 Posts
Discussion Starter · #3 · (Edited)
I think as per other posts on this issue, narrowing from the factory link pipe to the muffler would increase temp and back pressure, possibly limiting hp. Each engine is different, so only a before and after dyno run would tell.

Personally I would be looking for a muffler that doesn't have a restriction at the lower connector, allowing free-flow exhaust. Just my opinion.
I looked at a few other mufflers (including the famous Remus) for the K1300R, and they also have a 51mm muffler intake and outlet. So the restriction is not unique to Delkevic.
As per my previous post, Delkevic provided Dyno results showing a slight increase in HP and Torque, so can't be that bad.
I also measured the stock exhaust, and although the muffler intake size is a massive 63mm, the outlet is restricted to 43.5 mm. I can only guess from what I have seen that the 51mm size is common.
 
1 - 3 of 3 Posts
Top