Guzzitech B11 Y-Pipe

[Kev M]

CROSS POST FROM WG - my thoughts on the Y-pipe and Installation Instructions with my edits.

ONE NOTE - before removal, note the positions of the header retaining flanges. Some have flats that face one particular direction (I believe downward) and some don't appear to sit flush against the head. Look at this before you remove them and you'll be more comfortable with their positions afterward.

TODD's R&R procedure with my editorialization:

1. Put bike on side stand. (I did not start this way, I found it easier to start on the centerstand and then just temporarily put it on the sidestand when it was time to remove the old colostomy bag i.e. the old crossover/cat-con)
2. Using a 10mm deep socket with short extension remove the chin fairing. (4 bolts, 2 on each side to drop that plastic shroud)
3. Loosen the clamps on the head pipes. Using 10mm socket.
4. Remove muffler. Use 10mm socket on clamp and 13mm end wrench and 6mm allen on muff bolt Remove spring.
5. Unscrew the O2 sensor and let it hang. (I skipped this A. because I'm using a Guzzitech reflash and didn't need the 02 sensor, B. Because I didn't have a 22mm wrench or with enough of an offset or sensor socket to easily remove the sensor and C. Because my previously installed Phat-Duc made it easy to unplug the wiring and just drop the sensor with the colostomy bag)
6. Remove the bolts on the exh flanges and remove the head pipes. 13mm deep socket w swivel (I soaked these guys in PB blaster but was shocked to find them not only easy to loosen, but darn near only finger-tight. I didn't need a deep socket OR a swivel for this.)
7. Put an oil pan under the rear of the engine (I skipped this)
8. Pull the 2 hanger bolts and slip the “BAG” rearward as far as possible
9. Reach under the rear of the engine and unscrew the oil line from the oil pan and move to the side of the motor so it is clear of the BAG. (I skipped this and it was not an issue, maybe because I was still on the centerstand at this point I dunno.)
10. Now slide the BAG forward and down and it will slide out the right side providing you have a large drain pan. (At this point I had mostly dropped the colostomy bag but the centerstand was interfering, so with Jenn's help, I took the bike off the centerstand and extended the sidestand and it all but fell out the rest of the way on its own.)

11. Reattach the oil line.(Skipped, cause I never disconnected it)
12. Remove the seat and disconnect the positive cable on the battery.(Skipped the battery cable part, but I did remove the left sidecover for more access.)
13. Remove the cover on the starter using an allen wrench. (I did this earlier after Step 6 to unplug the 02 sensor wiring, I might not have been able to do it without removing the starter if I hadn't already done that some time ago when I installed the Phat-Duc.)
14. Using a 13mm end wrench unbolt the starter and slide it back. (Skipped this, thanks to Phat-Duc)
15. Cut the ty-wrap holding the O2 sensor. DO NOT CUT THE WIRE! Just let it hang. (Skipped this due to Phat-Duc.)
16. Reinstall the starter and cover. (Did this) And reconnect the battery. (but not this obviously)
17. Reinstall the seat.

Installing the new Crossover is a reverse of the above.
1. Place the new crossover in place. Hang it on the rear hanger. (This puzzled me, I did not hang it on the rear hanger because the crossover didn't come with any way to do so, i.e. there was no hanger mounts included on the crossover anywhere, just the pipe ends and a hook for the muffler pipe spring)
2. Place the clamps with split rings over the ends of the crossover. (I should note that the Guzzitech crossover DOES NOT utilize the stock Header Pipe-to-Crossover gaskets, and if they remained on the header pipes you should remove them first.)
3. Install the head pipes loosly do not tighten.
4. Align pipes side to side and the crossover front to back and check clearance.
5. Install the muffler. Checking alignment before tightening. Install spring.
6. Tighten clamps and head pipe flanges.
7. Install O2 sensor. (Todd kindly shipped my Y-pipe with a threaded plug installed in the O2 sensor bung since the Guzzitech reflash emliminated the need for it.)
8. Reinstall Chin fairing.
9. Check oil and fill as necessary.(Skipped for obvious reasons.)
10. Wipe header pipes down with alcohol to avoid spotting.(I did this, though I don't know why since my header pipes are all spotted lol. After one outing the crossover has started to take on that same petina but alas without the spotting, at least for now.)

My impressions:

Bike has a VERY slightly deeper rumble now, but otherwise basically seems to function and sound the same.

I'm sure exhaust gasses have picked up some velocity, and a feel with my hand suggested some physical change with what I feel coming out of the pipe at idle (volume, strength or speed of the pulses).

The lack of heat generating cat-con right under my feet was pretty obvious right away despite the fact that I was test riding on an otherwise borderline uncomfortably hot day (85-90F).

Truth is I suspect this will make the bike much more comfortable on 70-80F days, and bearable on 85-90F, though honestly at those higher temps the tank/tank sponsoons and small windshield all still block too much air and the then naked Jackal is more comfortable from a heat perspective.

Bike continues to run basically ping free and like a raped-ape as it has since the installation of the Guzzitech reflashed ECM.

Can't say for sure about mileage, but it appears that it will remain improved from the stock set-up (as reported after the reflash).

All-in-all I THINK (and hope and pray) that this bike has finally reached the point it should have been delivered from the factory - with only an additional $1000 or so spent on my part (not talking about BS accessories like HBs or heated grips), just talking about a reasonable map, and almost stock exhaust system, which probably puts out fewer emissions through a good part of the operational range (judging from the jump in fuel mileage over stock).

I give the reflash and the crossover ---> B) B) B)

If I didn't mention earlier the crossover itself looks like a very well made product.

 

[Rafael]

I had made similar adjustments to the removal/installation instructions, not necessarily better. Here are some I remember:

1) A standard socket worked fine for the header pipe exhaust flange.
2) I loosened the O2 sensor while it was still on the bike with a 7/8" box wrench. I cut a narrow slot thru the closed end of the wrench to get passed the wire.
3) Started the process on the centerstand. After removing the muffler loosening cat anchor bolts, I moved the bike off the centerstand and onto the side stand for the final cat removal.
4) Used a scissor jack to hold the Y pipe in position while I tightened the bolts.

I didn't notice much of a temperature change at my feet, the main reason I installed the Y pipe is to get the hot plate out from under the transmission/gear box. My bike's previous owner that didn't take care of it much, so I wanted to gain any advantage for longevity. I ran the bike without the muffler and found the exhaust to be completely muffled. There's no need for 2 mufflers... Not sure why MG designed two exhaust system layouts for the BNS12. I think the new EU Breva now use the NS12 layout.

The reason I selected the GT Y pipe over the other available brands, is that its the most symmetric and had the best flow path. The fit is perfect. The installation of an aftermarket product without having to modify it put a big grin on my face. :cheer:

 

[Kev M]

Yeah, I guess I didn't need deep sockets where told either, I forgot to mention that.

I also didn't think of slotting one of my box end wrenches, that's a good tip!

I also didn't use a scissor's jack (another good tip) since I had Jenn there to help.

As for temps, I don't recall ever getting an excessively hot reading on the trnasmission case with my laser pryro, that and the last time I changed the fluids they came out looking/smelling like new. I realize that's not the most valid test, but I had no real reason to worry about the cat-cooking the oil based on that.

I just didn't like how badly it cooked my feet and made me sweat waste-down on warmer days (though I might miss that heat on sub 50F days).

 

[Kev M]

CROSS POST UPDATE FROM WG - continued impressions of Guzzitech Reflash and Y-pipe


As of this weekend I've got a couple of hundred more miles on the B11 since the reflash (and the Y-pipe).

Fuel mileage remains good - either equal to or better than before. Though IRONICALLY I'm now pretty sure that mileage is BETTER when I flog it and worse when I ride sedately or steadily on the highway. I'm a little bit at a loss for that, except to guess that OEM mapping was ok at parts of the throttle where I am when I ride sedately (3-5k range) and perhaps too rich at higher rpms (where I go more when I'm thrashing it) and perhaps Todd backed some of the fueling down at that point.

Ambient temps for the last tank were around 79-80F and mileage was a little lower, closer to 40 mpg.

Ping seems to pretty much be absent still, which was the primary reason for this. Before the reflash it would likely have pinged just pulling away from a stop sign at 80F or even just rolling on a 5k rpm - and this weekend I would have had to lug it a couple of thousand rpm lower to get even the faintest evidence of ping.

Heat I THINK the heat coming off the motor remains about the same. I can still feel it and some laser-pyrometer checks seem to confirm this. HOWEVER that said, replacing the colostomy bag with the Y-pipe has DEFINITELY made the bike more comfortable in warmer weather. Though the tank sponsoons still act like a fairing and I can feel the engine heat, previously at an ambient near 80F my lower half would get uncomfortably warm and start to sweat. I remained "dry" and comfortable this weekend, and my mesh jacket kept the rest of me downright cool.

EDIT

Popping on Decel - I HAVE picked up some popping on decel now - I'm not compltely sure if it was there before the reflash/pipe or not, it could have been, but IF it was, it was muffled. Now it is audible. It is not horrible at all and doesn't really bother me, but it's noticeable. The exhaust note itself has a touch more base to it now with the Y-pipe and stock muffler.



Still I continue to give the reflash and Y-pipe ----> B) B)