new member with a Kerker 4 into 1 exhaust question

[88redmax]

I have an 88 model Vmax and have a Kerker 4 into 1 system arriving tomorrow. The bike already has the Dynojet Stage 7 jetting set-up and the V-boost eliminated. Right now it runs really well with the stock exhaust system. It put down 116 hp on a rear wheel dyno as is. I'm wondering how much this new exhaust will lean the mixture. I was hoping you guys have some insight on that. Also, while I was pulling the stock system off today, I was wondering about the heat shield that goes between the rear pipes and the gas tank. I'm betting the new pipes will have no mounting points for the heat shield. What have you guys done?

 

[SpecOps13]

I'm running a Kerker 4-1 on my 89. It has a modified stock setup in the carbs that I'm still dialing in. Right now, 152.5 mains, 0.032 shimmed stock needles. 3-1/4 turns on the A/F Screws. It is way rich. So much so that I'm running DRP7EA-9's and they are still black. I think 147.5's will put me in the ball park. This may or may not give you any insight. Since my bike is not a stage 7...

Toss the heat shield, no provisions for mounting it...

Good Luck, Hope this helps somehow..
Dave in Florida

 

[tugla]

im running also the kerker and stg 7. never dyno the bike but got 150 mikuni's 2 1/4 turns on the a/f , one shim and on clip 3 from the top. ran best while on clip three no shim. not sure if 152.5 jets wont be better, have slight issue around 7-7.8 grand if i go slow thru the rpm. plugs have always been nice tan if not a little lean (to me)

 

[tugla]

oh ya welcome to the forum man, you gotta post some pics when you get the pipes on

 

[Redbone]

Welcome to the forum! Like Dave said the heat shield can no longer be attached so you can put it in storage with you other stock exhaust parts.

 

[Rollie]

Welcome to the forum! Like Dave said the heat shield can no longer be attached so you can put it in storage with you other stock exhaust parts.

:rofl_200::rofl_200:

Welcome to the addiction !

 

[PATMAX]

Welcome to our party, now it's your party too! I was too lazy to research it but try to find out what elevation Dallas is above sealevel. Asking a guy in Colorado running the same set up may not be much help dialing in your mods. Unless you got an exhaust gas analyzer at your disposal, plug color is probably gonna be your best guide to richer or leaner settings. Seems most of us run rich. Power is made at the edge of leanness. If you are watching plugs closely, my opinion is to sneak up on leanness and you won't hurt anything. Don't expect to lean things out and run hard all weekend and burn or blow something up. Front wheel gets pretty light when your on the right track. Be sure to use the "search" feature on this site to learn from experience, mistakes, dumb luck. With that said, I better get out in the garage and drop my needles some more, I'm still rich @ sealevel. Stage one, 4/2/1 w/ comp baffle, no "Y", K&N filter and twitchy right wrist!

 

[SpecOps13]

Oops, Missed this, Welcome to our VMax Sand Box. Grab some toys and join in...:biglaugh:

 

[CaptainKyle]

Welcome to the forum