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1978 Exhaust

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mamalo65

1978 Exhaust

Hello Gentlemen,

I am now ready to get the pipes for my bike. A 1978 750 k. But need a little advice.
I have only been able to find Mac (001-1508) that has the right pipes. 4 into 2 turnouts/chrome.

Is there any other pipes out there?
I know eveyone has there own thing concerning pipes.

I am replacing the whole thing from the engine back.

Do I need to rejet the carbs? If so what size jets? Is there anything else I should look into replacing?

Worked alot of overtime and want to get everything I need to get the exhaust running great.

Bike engine is complete and she runs like a scalded dog.

I really thank you all for your help. I will try and get some pics posted.

Mamalo

TOOLS1

Re: 1978 Exhaust

Administrator

The MAC is a very nice exhaust. Cyclex has their own exhaust systems also. You might want to check them out.
As for the jetting. Every engine is different. Put the exhaust on, and try it. take some plug chops (readings), and go from there.
TOOLS

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1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
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mamalo65

Re: 1978 Exhaust

Thanks Tools. I looked at cyclex and they did not have the pipes in stock.
Found the MACS and they are on the way.

I really thank you for all the help you and the other guys have given.

Mamalo

mamalo65

Re: 1978 Exhaust

I replaced my stock exhaust with MAC 4 into 2 turn outs and now the bike is running bad.
When you give some throttle it is bogging down and then catches and she runs great. Until you back off and throttle back up then it bogs again.

Thought it might be the air mixture but adjusting does not seem to help and the carb gauges are all even and steady.

Tried re timing the bike and that did not work.
I believe I am going to have to re-jet the carbs for the new pipes.

Do you have any suggestions and if I need to re jet what size jets?

It is a 1978 750 K8 w/ the big carbs. All stock size jets.

Would really apperciate your help on this. I can't run it too much cause the new pipes will turn.

Thanks Guys.

Mamalo

TOOLS1

Re: 1978 Exhaust

Administrator

If you go to the cycle-x site they have a tec section, and it has a great article on re-jetting the carbs. Much more information then I could give you.
TOOLS

rusty vango

Re: 1978 Exhaust

In reply to this post by TOOLS1

i would humbly suggest a kerker 4 into 1 header,IF you run the proper muffler you need not rejet the carbs.also try to resist using "pod" air filters yeah they look cool BUT they are not whats needed ,use the stock air box instead