Some Exhaust-ive research on go fast parts.

Well My Motorbike friends, I've slipped on updates this past week. I was waiting on parts to arrive for the Ninja to make this post. While I was waiting I had a couple of busy work weeks and just couldn't get an hour or so to sit in front of the computer to pound out a new post. The parts arrived and I carved out some time in the shop to play around with the little race bike. Take a peak at the first part of a two part post on making the ninja a bit more peppy for the circuit.

An oddly shaped box arrived in the mail while I was at work. The shipper let me know that the package would be arriving after he had some trouble getting it packed safely. When doing Internet forum deals I appreciate a seller that communicates effectively and is straight and honest with me. The guy I did this deal with was a stand up guy. I was cruising the Ninjette forum at just the right time to find the contents of this box for sale and after mulling it over for a week I sent the seller a message and this deal was born.

These are Cobra F1 exhaust pipes for the pregen EX250 Ninja. Until now I have avoided any type of engine related performance upgrades. Mostly due to the fact that I am not taking advantage of all that the little Ninja has to offer currently. Since my 2004 Ninja is carbureted, modifying the intake or exhaust on the bike would require me to tune the carbs. Since I don't have a dyno handy, that kind of work has been out of my ability. I still don't have a dyno, but I am ready to try and add these babies into the mix. Many times I have been asked "what is that?" at the track. Especially now that I have removed the fairing and the decals. At the kart track they even checked to see if out was electric because it was so quiet. They don't allow electric bikes at the kart track. I wanted to give the bike a little more attitude and I think its time to have some fun with performance parts.

First things first I had to get the old pipes off. I have not touched the exhaust system for anything other than safety wiring the mounting hardware. The pipes do their job and are high enough to stay out of the way. Except for the overly quiet sound dampening, they work just fine. I pulled off the belly pan and removed the four bolts holding the cans on before popping off the exhaust system. The rear stand got in the way a bit, but it was a very simple process to get these out of the way and off the bike. While I was there I emptied out belly pan, as it collects a fair amount of road debris out on the track and checked to make sure I didn't have any oil leaks. All was good.

Here is a comparison picture of the two sets of pipes. The Cobra exhaust pipes are well made and very solid. I don't know when they were made, but I have to imagine that they are from at least a decade ago. They are a bit longer than OEM, but are significantly lighter. The stock pipes are 6.7 lbs each and the Cobra ones are 4 lbs lighter each. They mount the same way as the stock ones do. I ordered some new exhaust gaskets and am still waiting on them to arrive before I mount them permanently. This post mainly covers mocking them up to make sure they fit. The Cobra exhaust is noticeably lighter in your hands. The weight is low on the Ninja, but shaving another 6 lbs of the bike might make side-to-side transitions easier.

And here they are all fitted up and looking very good I'd have to say. The exhaust cans themselves had a few dings and a tiny bit of road rash from use, but that is fine by me. Both me and the little Ninja have just as much 'patina' as these pipes do. After admiring their cool look, I pulled them back off the bike and went over the muffler with a file and some 400 grit sandpaper. The cleaned up well without looking brand new spoiling the classic style that the bike has developed during my race modifications. I can't wait to get these permanently mounted and to hear them at full song hauling the mail around the track. Little by little the EX250 is getting more and more race focused. I have all of the take-offs from my race bike conversion, but to turn it back into a street bike would take some concerted effort.

While I was checking on the weight savings from mounting my new noise makers, I hauled out the aforementioned take-offs from the Ninja's parts bin to see what the ultimate weight savings turned out to be. My '04 Ninja 250 started out at a relatively light 355 lbs wet when referencing my Clymer manual. Wet meaning gas and oil in the bike. Some OEMs like to publish the weight of their bikes empty in order to pump up (or in this case down) the numbers and make the model look better. All of the stuff in the picture above is stuff I removed from the Ninja. Some of it went back on, like the shock linkage. I replaced some parts like the handle bars with lighter ones. All in all with the new exhaust I'll save 36 lbs of weight. The stock HP figures for the bike are 30 hp and 18 lb-ft of torque. Not exactly exciting numbers, but that 36 lbs will mean a lot to this little thing. My Yamaha wouldn't blink an eye at 36 lbs. Of course the FZ1 has something like 140 HP.

Part two of this story will come when the exhaust pipe gaskets arrive and I get a chance to install the Cobra cans permanently. That will also entail pulling the carbs and doing a bit of internet research on carb jetting. Coming up this Friday I have another trackway at Chuckwalla as well as a chance for some demo rides. The weather will be hot in San Diego county this coming week, but I'm looking forward to an extra day off to get a ride in as well. Take care Motorbike Obsessions readers, until next time.

Blue