The XS Triple Sidecar - a new exhaust

This was meant to be a fairly straight-forward build a new exhaust, do some maintenance and finally jet the sidecar right job. That was over a month ago. To be fair, I've built two exhaust, because the first one was rubbish, we will simply act as if the first never happened. 😉

That's what I started with – obviously the sidecar has already been removed.

As one can clearly see in the second picture, with the longer (and stiffer) shocks in the rear, the rear wheel can't be removed without removing the right silencer. This on its own wouldn't be too bad, but some numpty put a reinforcement of the sidecar subframe right over it, which makes removing the silencer a royal pain in the backside. 

Also I always I suspected that the bike would benefit from some sort of cross-over to increase low-end torque, which to be quite honest is the thing sidecar'ists like me care most about. Of course when taking the old headers off, the last few remaining studs came out as well, so now they're all made from stainless.

A new exhaust-bracket to position the silencer lower and further to the back of the bike to clear the centerstand. (Also take note of the still existing sidestand at this point.)

As I found out the hard way, every inaccuracy is multiplied by the length of the tube after it, the header bits were all trimmed to length on the lathe. 

A pleasant side-effect of this was that the fitup (of course) came out to be phenomenal, resulting in some text-book tig welds.

The bit that caused the biggest headache was how to make the inverted y-section, especially as it would be in full view all the time.

In order to get better access I then decided to remove the front forks and prop the bike up on the centerstand and subframe. When removing the forks, I found the fork gaiters to be in a way more desolate state than I originally noticed.

From the last picture to the ones coming up next was about a full day of work to fit up the tubing in a satisfactory manner.

... and when the flanges have dropped all the way down for the umpteenth time, you add some drops of filler to the backside to step them from doing that. 

Now I couldn't resist to do a little heat treating to the headers (yes, my neighbours still love me...) and gosh, do these flow better than the old stuff...

The last step in finishing the exhaust was to build an X-pipe collector. Not perfect for maximum throughput, but I have been more than willing to trade torque for horsepower on the sidecar. 

And that's the (more or less) finished header and X-pipe done. There's no realistic way to fit any more collectors on these headers anyway.

What I absolutely wanted was to have a bung to install my wideband to facilitate tuning the carbs.

Let's just say, my welding skills are proper hot. 😎 On a more serious note (as I found out the hard way), always apply PLENTY of copper-slip on both bolt and bung when welding in an AFR bung to prevent them from seizing during or after welding. If it burns off, it leaves PLENTY of carbon, which keeps things separate and ensures that everything comes apart smoothly. 

With all the bits laid out on the workbench it always looks a lot like next to nothing was achieved at all.

Really came to grips with the new welder finally - fused the db-eater (bored out to just over 1") into the silencer, so Mr. Policeman knows it's not easily removable. 

The installation-rubber-mallet is strictly mandatory of course. As was expected it runs a lot leaner down low, so shimming the needles and installing one size bigger pilots was necessary in order to make it idle properly again.

13.4:1 doesn't sound too bad, but that was after blipping the throttle and it would drop even further, making the bike very sensitive to oil- and air-temps. (Expect more wideband action in coming posts, I think this is a brilliant little toy to play around with!)

And of course, you want to hear it, don't you?

So what's the verdict? Big, big success. Usable torque now starts at about 2000 rpm and I can cruise around at 2500 to 4000 rpm, which makes the bike a lot more relaxed and economical. Also with the added torque, 5th gear is finally usable, which means I can actually use the bike on the Autobahn and cruise at 130 kph sitting in 5th at around 5000 rpm, not sure if there's a lot more to come beyond that, but the quite frank that'll do plenty for now...