Author Topic: Availability of After Market 4 to 1 or 4 to 2 Exhaust Sytems for 1978 750A (Read 9946 times)

saavejo · « **on:** March 21, 2013, 06:30:08 AM »

I am a new member to the forum and also just purchased a 1978 Hondamatic 750. This bike has an original factory 1976 4 to 1 exhaust which is was also used for the 750F model. Mine is rusted and I am looking for a aftermarket replacement. So far I spoke with the Mac and Vance Hines reps and they informed me that the 4 to 1 that they sell for the 750F model wont fit the 750A model.

I am looking for help from 750A owners in this topic. Also, If no 4 to 1s are available what is a good recommendation for a 4 to 2 system?
Thank you

raymond10078 · « **Reply #1 on:** March 21, 2013, 06:49:07 AM »

Good vs. available . . . I know MAC made a 4-2 system. I haven't heard anybody step and say that MAC is "the best", just OK.

http://www.ebay.com/itm/Honda-CB750-A-Hondamatic-4-2-Exhaust-System-Chrome-Pipes-Mufflers-001-4109-/160832256551?pt=Motorcycles_Parts_Accessories&hash=item2572597a27&vxp=mtr

Pricey!

There's at least one 750F system on ebay right now, too.

Gregorymoto · « **Reply #2 on:** March 21, 2013, 08:02:24 AM »

Are you sure that is a stock 4 into 1?

saavejo · « **Reply #3 on:** March 21, 2013, 09:28:10 PM »

Thanks for the response on the 4 to 2 for the A and the 750F. Yes the 4 to 1 that I have is a stock Honda 4 to 1 1976, which was also shared with the 750F. The left side touches the bottom of the oil pan. I am not sure if the Mac or other aftermarkets 4 to 1w ill fit the A model. Thanks!

Gregorymoto · « **Reply #4 on:** March 22, 2013, 07:46:45 AM »

As far as I know you can run any set up on it. If it's the same as the 75F you can run whatever SOHC 750 pipe. I have an F and I have had Vans and Hines - RC- MAC- and now Yosh on my bike. On the K's I've owned they are all the same more or less. The only issue you might run into is bolting down the hanger on some, but thats not a big deal.

raymond10078 · « **Reply #5 on:** March 22, 2013, 08:59:16 AM »

The sump on the A creates clearance issues with most exhausts. For example, It was reported that the cyclex 4-2-1 will not fit. The point - be careful!

Jerry Rxman Griffin aka MuthaF'er · « **Reply #6 on:** March 22, 2013, 09:16:00 AM »

Is your muffler or the header your issue? Mac makes a replacement muffler. The mounting hole may not match up but you can improvise that as we do with the Kerker.

saavejo · « **Reply #7 on:** March 22, 2013, 10:46:14 AM »

Thanks for the resposes

. I prefer replacing the complete unit but please provide me with the manufacturer and P/N of the muffler as an alterrnative. My bikes headers had surface rust and i went ahead and cleaned them up and painted them black. The muffler has a couple of small hole on the bottom which I repaired with JB weld. So far is holding up. I having a hard time envisioning any issues of utilizing a 4-1 1976 750F aftermarket exhaust for my Hondamatic when I have an OEM Honda 750F 4-1 installed on my Hondamatic. I probably need to contact the MAC rep.

If you have an aftermarket 4-1 installed on your hondamatic or your 750F (F0, F1 models) please let me now the manufacturer and P/N. Thank you and best regards

Jose

raymond10078 · « **Reply #8 on:** March 22, 2013, 03:19:55 PM »

I just checked the Honda parts fiche - and while the 76 750F exhaust looks the same (from the side) it differs quite a bit underneath. The 76 750A exhaust is narrowed almost immediately, well in front of the muffler. That sump is REALLY in the way of most exhausts.

raymond10078 · « **Reply #9 on:** March 22, 2013, 03:38:29 PM »

Also - the outlet of the 76 A exhaust headers is 2.5 inches - which is quite large - compared to most aftermarket mufflers.

Not that the door is closed on that idea - but the choices are fewer.

Here's a Supertrapp example:

http://www.supertrapp.com/product_sections/detail.asp?CatID=38&ItemID=425-25190

I've seen others use car mufflers (not on a A - but on smaller 400/450 twins) - as in a cherry bomb, or similar.

saavejo · « **Reply #10 on:** March 22, 2013, 10:31:29 PM »

Thanks for all of the responses, help add suggestions! According the the microfiche I have the F model installed on my 78 hondamatic not the 76 A model. The left pipe is touching the oil sump on mine as it goes into the 4 to 1 manifold. The 4 to 1 manifold clears the sump. I like the sidewinder at Cycle X. I think is a Vance and Hines P/N 1401-P. I would consider it if I could install a baffle in it. Your comments and suggestions are welcome. Do you think a baffle is available? Will I have to adjust the carbs or rejet if I decide to go with the sidewinder?

Thank you, I appreciate all the help

chickenman_26 · « **Reply #11 on:** March 26, 2013, 08:17:30 AM »

If you can find a stock exhaust for '77 or '78 750A, even if the mufflers are rotted, you can replace the mufflers with a pair of Dunstall replicas sold by EMGO. I've seen them on a '78A, and they almost looked stock.

Stu O

raymond10078 · « **Reply #12 on:** March 26, 2013, 11:29:19 AM »

Stu is right . . . of course.

Anyway - here's a bike that uses the stock 77/78 exhaust headers - with aftermarket mufflers.

saavejo · « **Reply #13 on:** March 27, 2013, 09:08:38 PM »

Great suggestions! The headers or pipes are not rusted thru however there is surface rust which I am cleaning and plan to paint semigloss or satin black. The EMGO Dunstall will look nice and its is reasonably priced! Thanks so much guys

saavejo · « **Reply #14 on:** March 30, 2013, 09:53:10 PM »

Hello Kandrtech,
I really like the looks of the cycle-x sidewinder (V&H ) Is a nice 4 t0 1 however is open w/o a baffle. Will I have to change the jets on my hondamatic or do anything else to it if I install the non baffled sidewinder? Do you know if they sell an aftermarket baffle for it?
Thank you very much

raymond10078 · « **Reply #15 on:** March 30, 2013, 10:43:34 PM »

Suggest you call cycle-x for baffle question.

Yes you would have to rejet.

saavejo · « **Reply #16 on:** April 07, 2013, 08:01:59 PM »

Thanks, I will call Cycle-X.

V8rider · « **Reply #17 on:** April 14, 2013, 08:29:37 PM »

Here is V&H exhaust on my matic build fits great

Jerry Rxman Griffin aka MuthaF'er · « **Reply #18 on:** April 14, 2013, 08:35:52 PM »

Is that V & H from a DOHC?

saavejo · « **Reply #19 on:** May 02, 2013, 08:26:39 AM »

I am backwith more questions

I am looking at the Mac dual exhaust p/n 001-1308 and 001-1508 The 1308 is listed to fit the the cb750 k from 1969 to 1976 and the 1508 is listed to fit the CB750 k 1977-78 and the 750F 1976 to 1978. Which of these two will better fit my 1978 750A? My concern is the clearance of the oil sump pan. I can work with the foot peg bracket. Thanks in advanced for your help!!!

MRieck · « **Reply #20 on:** May 02, 2013, 08:45:46 AM »

Quote from: Jerry Rxman Griffin on April 14, 2013, 08:35:52 PM

Is that V & H from a DOHC?

Gots to be Jerry....the one on Sam's bike is.

raymond10078 · « **Reply #21 on:** February 17, 2014, 08:41:09 AM »

Just wanted to share - found new exhausts that fit our A bikes on cyclexchange today:

http://www.cyclexchange.net/Honda%20SOHC%20High%20Performance%20Exhaust%20Page.htm

saavejo · « **Reply #22 on:** February 20, 2014, 07:21:47 PM »

Thanks for the info, Nice dual exhausts from Cycle X!

Grnrngr · « **Reply #23 on:** February 20, 2014, 08:02:01 PM »

Mine came with aftermarket 2-1's, I'll need to check but I think they are Jardines.

karter · « **Reply #24 on:** February 21, 2014, 11:27:43 AM »

Here's a picture of my 1978 CB750 A with Mac 2/1 pipes with Emgo Dunstall mufflers . The second pic shows my 1977 CB750 with the stock exhaust and the 1978 with the Mac/Dunstall combo .
I don't know if Mac will sell the 2/1 pipe set only but their mufflers leave a lot to desired in the looks dept.

News:

Author Topic: Availability of After Market 4 to 1 or 4 to 2 Exhaust Sytems for 1978 750A (Read 9946 times)