skillzman1
XS400 Junkie
not welded....should slide off at the coupler...otherwise you gotta cut it...sawzall style.
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MAC 2 into 1 Exhaust Install
- Thread starter Vlad
- Start date
Why was the video removed?Im thinking about the same system for my bike also.
It doesn't need a video - I have one on my bike. Pops right on, just get new exhaust gaskets. Oh, mine also needed a little massaging to get the pipes to the correct size, nothing that a little elbow grease couldn't deal with.
gregdaybreak
XS400 Member
I just did this install on my 78 XS400E
It was pretty easy but I was getting a little exhaust leak on the left side so I bought new copper exhaust gaskets and put them in and now everything is working great!
I rejetted the carbs. Stock in my bike for the main jets was 132.5 and I put 142.5's in and raised the carb needles up one slot. Turned my mixture screws out 3 turns and synced the carbs with the homemade manometer and it runs great and has some good power and sound. The old pipes were rusted through in spots so it is such a big difference!
It was pretty easy but I was getting a little exhaust leak on the left side so I bought new copper exhaust gaskets and put them in and now everything is working great!
I rejetted the carbs. Stock in my bike for the main jets was 132.5 and I put 142.5's in and raised the carb needles up one slot. Turned my mixture screws out 3 turns and synced the carbs with the homemade manometer and it runs great and has some good power and sound. The old pipes were rusted through in spots so it is such a big difference!
gregdaybreak
XS400 Member
Here is the bike with the exhaust on it. Sorry it is a bit blurry
If you do this conversion is there any mods that need to be done to craborator?I read of people rejetting it is neccesary or are they just doing this for better performance?
gregdaybreak
XS400 Member
I rejetted the carb and adjusted the needle. I think it really depends on a lot of things (altitude, current jets, condition of carbs). I actually installed the MAC kit on my bike without adjusting the carbs but I bought a jet kit from 6sigma on ebay and he sent me 142.5 jets and told me to raise the needle up 1 notch and then turning the mixture screws out 3 turns. The bike is a lot faster now! Before I rejetted the bike would start up great but when it was warm it would slowly lose RPM's and stall out. Now it is steady and has some great power so I would recommend just picking up the jets since they are cheap (try mikesxs) and throwing them in only if there is some performance issues after the install.
Well Im not sure what route Im going on my pipes yet.I first considered the mac 2 in 1 but powder coated with ceramic.Im also throwing around the idea of rerouting my pipe over the crank case so I can have a trail cobination street bike.
The carbs are getting taken off for rebuilding and cleaning so while I have them apart I might as well rejet.I know everyone likes more performance.
So with the 2 in 1 install did you get more top end power?My bike has alot of low end torque right now but seems to stumble after 60mph.
The carbs are getting taken off for rebuilding and cleaning so while I have them apart I might as well rejet.I know everyone likes more performance.
So with the 2 in 1 install did you get more top end power?My bike has alot of low end torque right now but seems to stumble after 60mph.
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gregdaybreak
XS400 Member
Yeah I noticed that it has a lot more power now. It also starts and idle's better. Once I replaced the exhaust I pulled the carbs and cleaned them pretty well before rejetting so I am sure that also helps.
I like the idea of the 2 in 1 exaust.
1 it removes the H pipe inbetween the 2 exaust pipes.
2 only 1 muffler.
3 more torque and power.
4 Cheaper than my other idea of having my pipes bent to make a combo street/trail bike.
5 No welding except maybe muffler.
6 Easy installation.
7 Looks better than stock.
1 it removes the H pipe inbetween the 2 exaust pipes.
2 only 1 muffler.
3 more torque and power.
4 Cheaper than my other idea of having my pipes bent to make a combo street/trail bike.
5 No welding except maybe muffler.
6 Easy installation.
7 Looks better than stock.
Ratfan
Ratfan
Hi Guys I am a newbie here and have just read the article about the Mac2 exhaust system.Over here in the UK it's pretty fair to say that all systems have been used up now and even our some say hated others beloved Motad systems are no longer listed.So does anybody know of a good Stateside supplier that would ship to the UK preferably via PayPal payment but that could be got round.My model is a 1981 XS400SE US Custom,apart from the bars which I have changed in favour of 16 inch apes she is original all be it she does have one of the aforementioned Motad systems that resembles the work of an apprentice spider!!! To that end there is no chance of getting her through our tough road worthy test!! Left to me she would run on home made drag pipes but that's a no no for the test!! I thank everybody in advance for any help in this matter and think I am going to enjoy this site a lot.Cheers for now Ratfan (Andy) Hunting this system is like this little guy!!!
sayosen
XS400 Addict
I am looking for a 2 into 1 set up for my '78 xs400 as well. I have gone through the Mac Performance site and I can not find one fo my bike; in fact, they don't list any Yamaha models. Can you you guys tell me which model exhaust you used or if you ordered it from a different site? Thanks.
sayosen
XS400 Addict
Thanks for the quick reply, bcware. I was a bit concerned about doing buying an exhaust listed as "Mac" on ebay since Mac Performance doesnt even list one for the 400, but if others have had good experiences, I might take a shot. It's only money, right?
I don't think it is fake or anything. Mac seems to be the only company to make aftermarket headers for these bikes as far as I can tell.
http://www.bikebandit.com/mac-2-into-1-megaphones-exhaust-system?m=147198
Bikebandit also has the system if you feel more comfortable buying it from a large reputable site; it will only be slightly more expensive with shipping.
Just enter your own year, etc into that site to make sure fitment is ok.
http://www.bikebandit.com/mac-2-into-1-megaphones-exhaust-system?m=147198
Bikebandit also has the system if you feel more comfortable buying it from a large reputable site; it will only be slightly more expensive with shipping.
Just enter your own year, etc into that site to make sure fitment is ok.
sayosen
XS400 Addict
Thanks for the link - that looks like what I need. I found one listed on ebay with a part number, which I then plugged in over at Mac Performance. The search results indicates 2 into 1's for Honda's and Suzukis. I shot Mac an email inquiring about ones for Yamaha - I will post their reply when I get one.
I'm having some trouble installing my new mac 2-1.
I bought some new exhaust gaskets (they are not copper, but look more like aluminum or something bright and silver).
Anyway, I can't get all the flanges on the studs. 3 of the 4 barely make it on far enough for me to get a nut on there, but the final one just won't go in.
Some of the photos on here show the flanges very close to the engine when the system is tightened down, but mine will seriously hardly even get on.
What's the deal? I've rotated the flanges and it doesn't help.
Are you not supposed to use a gasket? Even if I didn't use one I can't see how the pipes could go in as far as Vlad's bike is showing.
I have a 1978 2-e.
I bought some new exhaust gaskets (they are not copper, but look more like aluminum or something bright and silver).
Anyway, I can't get all the flanges on the studs. 3 of the 4 barely make it on far enough for me to get a nut on there, but the final one just won't go in.
Some of the photos on here show the flanges very close to the engine when the system is tightened down, but mine will seriously hardly even get on.
What's the deal? I've rotated the flanges and it doesn't help.
Are you not supposed to use a gasket? Even if I didn't use one I can't see how the pipes could go in as far as Vlad's bike is showing.
I have a 1978 2-e.
It looks like the "trouble" stud was slightly shorter than the other 3; about 3 or 4mm. It was simply tightened in more than the others. I've always had trouble with exhausts on this bike; even the stock pipes. When fully tightened the stock system barely allowed the nuts to sit flush with the studs, but I have never had leaks or anything.
I pulled all of the studs out; they're about 45mm long. I am going to buy some new, longer ones so I don't have to fight with this thing every time I do an install.
I pulled all of the studs out; they're about 45mm long. I am going to buy some new, longer ones so I don't have to fight with this thing every time I do an install.
