Delkevic 4 into 1 exhaust note 1980 cb 750 w/o baffle

[@ronchambers7972]

Wish you were my neighbor so I could hear you harass that thing up and down the street.

[@chrystofercarson3954]

I have a 1980. Did you only open up the main jets or did you open them all to be bigger??

[@nathanbrisson8515]

Just the mains. They were hand drilled using a pen vice and a very small bit from an index drill set. The drill bit I used was the next size bigger that would not fit through the oem jet. Super easy. That was my first one, I recommend actually getting a few sets of jets for your application that are incrementally larger. These will be good to have on hand when trying to dial in carbs with pods. Test run with fresh plugs, pull plugs after a thorough warm up and ride. See: plug chops. Adjust with jetting as necessary. The cv carbs seem to be more finicky with pods than the older manual slide carbs. Be patient.

[@chrystofercarson3954]

So if I see the plug chop should I go with a bigger jet or smaller?? And once dialed in did your bike have any lag in rpm ranges with just the main jet being bigger?? Or was snappy throughout the entire rpm band??

[@nathanbrisson8515]

@chrystofercarson3954 -no problems, it ran hard. I remember having one issue early on in the carb process, my tank wasn't venting properly. So it would run decent for a bit until it warmed up, I thought. But it was pulling a vacuum lock and then it would run crappy and I'd scratch my head. The time it took to vacuum lock upon first starting cold It acted like an electric issue upon warm up... Always check the easy stuff first. Make sure all your floats are set correctly, jets and passages are clean, and start with new plugs. I needed to rebuild the petcock on the tank (carb clean and an 8$ kit with a gasket and an o ring). Basically, I guess what I'm trying to say is all aspects of induction and ignition have to be titties. We're taking apart 40 year old carbs that have brittle hoses, brittle manifold boots, crunchy plug wires, potentially funky coils, there are so many little boxes to tick before the jets. Don't forget all those things. Did it run like it was supposed to before we took the original airbox out?

[@ATrustInThrust]

That sounds great! Did the pipes fit well under the bike? Not too low?

[@chriszz22]

Does your bike have the stock cams in it? It Sounds great!

[@nathanbrisson8515]

Yes that bike was stock except for exhaust and carburetors. The stock configuration in those vacuum carbs are very lean. I ran pods on it..everyone that can't tune carbs says this is impossible. Those have pressed in pilot jets. So you have to open them up significantly by hand drilling them. Ran like a beast.

[@trevorschell5530]

@@nathanbrisson8515 what size main jets are you running ?

[@nathanbrisson8515]

@@trevorschell5530 1 size larger than stock. I hand drilled them.

[@lucaskn8192]

Wow, amazing sound. Since you have air pods, what size Jets are you running? Did you "fill up" your pods with a washer or similar?

[@georgisgarage]

the video with the washers is a troll...please dont do that. Tinker and tinker until you get the jets right

[@nathanbrisson8515]

The 79 twin cam has the vacuum carbs w pressed in pilots. What i did was using very small index drill bits and a pen vise, found the bit that fit, then increased the diameter by hand drilling until i opened up it two sizes.