Rejetting not necessary with a Delkevic 4 into 1?

[mattd1205]

I decided to get a Delkevic 4 into 1 with the classic straight muffler for my ‘78 GS750. the instructions say you don’t need to upjet if you’re running a stock air box, air filter and use the supplied baffle. Is there any truth to this claim?

Thanks
Matt

[Pipefighter]

I'm looking at the Delkevic for my 79 GS1000E. I had read somewhere that they dyno the actual bikes, so I got in touch with Delkevic. They confirmed it. System designed to work out the gate with stock air box. No fuss, no muss. If the buyer then wants to run pods/velocity stacks etc..., then all bets are off.

[Deuce]

I didn't re-jet mine, as per instructions.

[OldVet66]

I was already re-jetted for pods and a V&H 4-1. Dialed in beautifully and much easier to tune than the V&H.

[mattd1205]

Excellent! Thanks for the info guys!

[mike10]

I have a 1980 GS1000 stock everything BS34CV carbs with the Delkevic 4 into 1, I had to rejet. I think Steve and some others on the site helped me figure out what I needed. Cant't remember what size I went up to. But I did have to install larger jets.

[TeamDar]

Any motorcycle that I have installed a 4 into 1 header on has required rejetting. If it didn’t then the header didn’t improve the flow.

[Steve]

The Suzuki pipes were remarkably efficient, so just changing the exhaust might not make that much of a difference.

The airbox, however, ...

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