Scored a 4-1 for my 79sf...

[Shuriken]

I got the 4-1 today. A bit more rust than I expected, but chrome cleaned up well. Pretty good deal for $75 shipped, considering new are $350ish.

I will try to have it installed by tomorrow so I can let you all know what difference I find.

Ben

[Dan Hodges]

Originally posted by ae7f
I got the 4-1 today. A bit more rust than I expected, but chrome cleaned up well. Pretty good deal for $75 shipped, considering new are $350ish.

I will try to have it installed by tomorrow so I can let you all know what difference I find.

Ben

Nice price. There is a company called Jet Hot that acid cleans and coats headers with a heat proof Ceramic coating. They are cheap and the headers come back looking better than new. I have a set of Super Trapps on my XS. I have had them on and off several times and it definately makes more power with them than without. Nothing sounds better than a 180 degree in line four with a four into one exhaust and the wick turned up. Not even Aerosmith comes close.

[grifff]

..

Good deal Ben. I ordered mine today along with a bunch of other stuff from 3 diff web sights. I decided on the Mac 4-1($325) and hope that i don't have to pull the pipes every time i change oil filter.

[Shuriken]

Agreed. I just decided I like the 4-1 sound much better.

I think my bike sounds modern, now. Higher and whiney. But I can really hear the combustion cycles very well. The bike idles great, too.

But wrapping her up and listening to that pipe whine is one of the better sounds I've heard in a long time.

The 4-1 versus 2-1x2-1 sound is completely different. I love the new sound.

Power is different. Can't say for sure because I don't have the carbs dialed in. I have a flub spot just off idle and somewhere in the midrange. When I get rid of those problem spots and can feel the pull all the way through, I'll be able to decide.

However, for now, when I wrap it up into the high midrange - high rpms, the bike seems to pull like ..... well, insert anything mean, here. It accelerates very, very fast in high rpm. Plus, did I mention I love that 4-1 whine?

But pulling a passenger makes the bike feel slow. Hmm.....

In comparison to my 80g standard with the dual 4-2 pipes, the standard seems to lug around at low rpm much better and it wakes up out of idle much better. I think it would lose the race in the mid to high-mid range compared to the 4-1 79sf.

However, I will try carb tricks, too. My 80g carbs are set up pretty well. Maybe I will try a carb swap.

Funny thing is, on the 4-1 79sf, colortuning (killing engine at speed to look at plug color) the plugs today revealed some curious inconsistencies. #2 and #3 were more towards white color at mid-full ranges while the other plugs were tan. Weird. At idle the bike is rich. Also, I think the bike is rich during a tiny spot in midrange, too (where the midrange flub is). I had the needles set up for the dual 4-2 setup (and the pipes were leaky and had no baffles). So I may need to adjust the jet needle positions for one thing. Of course this is after I determine if the main jets are the right size.

Hellacious mid and top rpm performance with the 4-1. Beautiful sport bike sound. Very quiet exhaust note at low speed. Easy to hear what the engine is doing with a quiet pipe.

However, the baffles rattle a bit in this pipe. Hmmm... not sure if I can fix that yet or not. Doesn't bother me too much though.

I attempted to colortune (with the Colortune) the idle mix and I did balance the carbs. But I may have to jet and adjust before I could comment for sure about the differences.

My 80g runs really well, even though it smokes like a .... All I know is the 4-1 feels like it breathes a lot better, it is quiet, and it seems that it opens up the mid-high rpm ranges.

If I get a chance to have another experienced rider race me (him on my 80g, me on my 79sf) in a safe location, I could make some more comparisons.

Overall, love the 4-1.

Problems:
1. Installation was tight. Rear brake lever when released touches the pipe. Haven't solved this yet.
2. Had to put a lot of pressure on the exhaust system to pull it far enough to the side of the rear axle for enough clearance.
3. Pipes immediately yellow/blue. Not such a bother to me, but it did happen.
4. Pipes to ground clearance is very tight. Easy to scrape them on bumps and stuff. Riding 2 up may consistently ding them. I have rear shocks on highest preload and will have to tighten up the front end.
5. Oil change / rear tire removal may require removing the pipes.

Most issues aren't such a bother. This 79sf is my play/sport bike. Less weight, lower seat height, smaller tank, no luggage racks, bars, etc, 4-1 for high end power.... The 80g is unparalleled for riding 2 up, utility riding, interstate, luggage, comfort (king/queen seat), etc.

Ben

[thumperjsa]

As for my Mac 4-1, I just did a rear tire pull in mine and clearances were fine. I did take my centerstand off though. I could put it back on and use one of the stops that were supplied to keep the centerstand from hitting the muffler. But since I don't use it much, I never re-installed it.

[Shuriken]

Oh yeah, that reminds me of problem #6: Centerstand contacts the pipes. Need some rubber stoppers or something.

Ben

[thumperjsa]

When I go my pipes, it came with 2 different length black l-shaped bars. I did not realize until after I decided to remove the centerstand permanently, that the bars were stops.

[Dan Hodges]

4 into 0ne header

Super Trapps are the best, they have double wall construction,(don't turn colors) have mechanical baffles(no fiberglass) and tuneable/removeable plates in the muffler.They clear the centerstand, oil filter with Lockheart oil cooler and or other wise fit like a glove. The pecking order is worst to best, Mac, Jardine, Kerker and Super Trapp. Kerker is everything the Super Trapp is but it's not of double wall construction(it turns blue with age). The Super Trapps and Kerkers are still out there but you have got to call around. I have been looking at XS Elevens for over a quarter of a century and have seen every exhaust pipe abortion there is and when I read about what you guy's are going through, I can only shake my head in disbelieve. Mac is to exhaust systems what Iskenderian is to cams,they make something for everthing but none of it is worth a -- yes you got it.

[Shuriken]

Had a chance to ride my 79sf 4-1 again this weekend. "Oh what fun it is to ride...." oh, I'm a bit early for that, sorry.

I didn't have time to tinker with the carbs and jets and such. I only had time for a short experiment.

My bike lugs off of idle, then it's like a switch kicks in and the bike seems to run normal. The bike also lugs in the midrange, but when it finally stops lugging (my tach and speedo don't work yet, so I don't know the RPM range) it is like a switch kicks in and all the sudden the dashed lines on the road seem to start flying by and it feels like a 2-stroke power band.

So, I have 2 dead spots. The bike idles fine on the pilot circuit. I also have synched the carbs really well with my trusty Carbtune.

I didn't have time to tweak, like I said, but I'm guessing it's really rich just off idle, and lean in the midrange.

Reasons:
I think it's rich off idle because the diaphragms had holes in them. I repaired with the rubber spray, but they might be a bit too stiff. I have another set of carbs (78e) but haven't done a swap for testing. Also, plug color seems to support richness off idle.

I think the midrange is lean because I don't remember where the jet needle positions are at. I think I had set them a notch lean from the middle position for the 4-2 setup with stock airbox and filter. Also, to experiment, I removed the airbox/filter and took the bike for quick test and it really flubbed in the midrange, even more than with the airbox installed. I did not have time to examine plug color.

Also, above midrange, the bike seems to really wake up. I think that is because the mains have taken over.

So my plans when I get time are to make sure that the mains are good (not sure exactly how to do this without obscenely breaking the speed limit for WOT) and then simply adjust the jet needle positions to richen up the midrange.

I may have to get new carb diaphragms or do a swap or something and verify the float levels for the off-idle bog.

Good winter project. Both of my XS bikes are garaged for now. Did my last 70 mile ride for the summer. The mountain pass I traveled had quite a bit of snow. Tad bit cold at 7000ft.

My 79sf with the engine in the shape it's in, with decent carb tweaking, would kill my 80g in a race. But my 80g is tired, needing valve and piston/ring work.

Ben

[thumperjsa]

I am in the middle of doing my oil change for my bike with the MAC 4-1. The header pipes make it a little tricky to get to the oil plug but it is accessable. It is easier to get to if you take the oil element cover off first though. The cover does not come strait through the pipes as I first thought.

I had to loosen the bolt all the way, then lower the cover. After that, I slide the oil cooler plate out of the way and then turn the filter cover about 45 degrees and it pulls out in between the pipes.

I also am picking up a couple of o-rings for the cooler plate and filter cover because I am getting a bit of a leak from that area. I was able to find a couple of o-rings at my local yamaha dealer. Of course they are $7.50 each. I also ordered a new oil cover bypass bolt because the part where the cocket makes contact is a little chewed up. Looks like a PO tried to take a standard socket to it rather than a metric socket. Gonna also replace the oil plug to while I am at it. I noticed there is no washer on the bolt when I pulled it.

I plan on going on a ride for the vote rally tommorow in West Palm Beach and I don't want a oil leak smelling up the area.

[skids]

The Jardine 4-1 is the same way on my 81H. Unscrew the bypass bolt a little, push the cup back up, unscrew the bolt some more, push up the cup. Eventually, you have an oil mess! I am going to put a small drain plug on the filter housing to control the mess. I have a spin-on adapter on my model E that also has the jardine 4-1's (works well), but there is not enough room on the model H for the spin-on adaptor and filter...the head pipes cross too close to the bypass bolt.

Originally posted by thumperjsa
I am in the middle of doing my oil change for my bike with the MAC 4-1. The header pipes make it a little tricky to get to the oil plug but it is accessable. It is easier to get to if you take the oil element cover off first though. The cover does not come strait through the pipes as I first thought.

[grifff]

...

I think this is a problem with all 4-1's with oil coolers.

[John]

There is an aftermarket by pass bolt available that has a 17mm hex head vs the 13mm of The OEM bolt. I have replaced mine and it has been great. No problems at all and you don't have to worry about rounding it over.

[thumperjsa]

I need to check but I think my bolt is 19mm, not 17mm

[John]

My mistake...the drain plug is 17mm, and the bypass bolt is 19mm. Sorry...