Kerker Slip-On's?

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backfire

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As many of you guys know, I've been waiting on the new Max to come out and I've also been trying to find a HDSE forever, but for whatever reason, I just haven't found the one I want yet. Soooo, it looks as if I'll keep my '95 for awhile longer (at least for this Summer) so I'm in the market for some slip-on's for the bike.

Back in 1989, I had a 4-2-1 Kerker Exhaust System on my 1985 and I just loved it. However this time, I'd like to install the Kerker exhaust again, but I'd like to keep the stock 4-2 exhaust system configuration, over going with the convential 4-2-1 Kerker design- just to keep exhaust outlet symmetry on both sides of the bike for asthetic reasons.

Does anyone know if Kerker produces slip-on cannisters for the stock header that will retain the 4-2 design?

Thanks gents! :)



-john
 
theres a guy in the town over from me that has that setup and i can honestly say i dont like the way they look or sound. believe it or not i actually like my trash cobra's sound a lot better. And that is way too expensive for slipons come on for a little more you can have a real full system
 
I know for a fact the Cobra's are much better looking and sounding, but I also heard that they are so much lower backpressure that the jetting needs to be downsized a bit or the bike runs way too rich.

That's what I was told, anyway. Sitting and listening to it, it was really good sounding. Much better than the Kerkers in my opinion.

Regards,
Tom
 
Thanks for the link "eatatjoz". :)

I've never had any Cobra stuff, except on my old Honda 350x trikes back in the day and although they were inexpensive, they were *loud* and they rusted once the cheap paint burned off.

If their slip-on's for the Vmax are as loud as that was (or even louder) and if they have the same cheap build quality as what I had before...I don't want them. I prefer a more subdued, deep exhaust note over a screaming, raspy sound, plus the cans must come in chrome. ;)

Personally, I think the Sidewinder System from England is the trickest slip-on for the Vmax, but I emailed them for a price and the cost was well over $1100, because of the poor money exchange rate the USA has right now. It looks like they have a great product, but the crappy value of the U.S. dollar kills their sales to U.S. customers according to them.

EDIT: I went to Cobra's website and looked at what they had to offer- the Slashcut type? I see they do come in chrome and do they have any sort of baffle inside of those cans? I'd think there would be, but the website description doesn't say much about them.


-john
 
The cobras i have came on the bike when i bought it. they do make it run too rich and you would need to change the jetting if it bothers you, mine runs rich but it still runs good. Its too bad i dont have the money yet or i would sell these used to you when i step up to a full system. They look and sound good but they actually knock off about 10 horsies if that matters to you. they arent cheaply made whatsoever, and the chrome is pretty tough, i actually had some bugs burn onto them and the only way to get it off was steel wool and soapy water and it didnt leave any scratches. In my opinion the cobras are your best bang for the buck if slipons are what your after. They are only LOUD when you open it up, when your cruising through town or just riding normally they arent nearly obnoxious enough for me

http://www.youtube.com/watch?v=bHBeRMpkyVg
 
oh i forgot to add that these pipes do have a baffle in them but you cant change it or remove it
 
Thanks for the info guys and based on what I've read here, seen/heard online about the Cobra Systems, etc.- I'm getting the tried and true Kerker slip-on's.


Here's why~ (and this is the engineering in me coming out again...sorry)

1. If an engine runs richer after an exhaust system change and everything else is equal, than the airflow through the engine has to have slowed down- i.e. greater backpressure. Engine airflow dynamics state that when airflow within a piston driven engine increases, BSFC (Brake Specific Fuel Consumption) must increase also in some proportion to maintain the correct desired AFR. (Air Fuel Ratio)

Soooo, if the Cobra System makes the engine go richer after it's installation and as one poster stated that the power actually dropped by 10 HP or so, it stands to reason backpressure has increased somewhere, where airflow has decreased, BSFC has gone down and the power falls off because of it. Conversely, the Kerker System actually requires *increased* jetting, which indicates the exact reciprocal of the Cobra System- which is a good thing, indicating more airflow through the engine, which obviously makes more power as a result. No thanks on the Cobra stuff...


2. The Cobra Systems do not have any sort of "adjustability" in their packing/silencer design like the Kerker Systems do, therefore, you get what you get, whether you like it or not. Again, no thanks to the Cobra stuff...


I'm not knocking anyone's parts over another, I'm just analyzing both systems from a engineering point of view, rather than a monetary one, so I can get the best bang for *my* buck in not only price, but also in performance/design.

Sorry if it seems I over-analyze everything to death...I don't mean to be difficult, I'm just hard-wired that way from engineering training/education over the years I guess. It's just my way... :icon_rolleyes:
Thanks again for all your opinions. :cheers:


-john
 
well thats cool thats why im getting rid of the cobra's but if your wanting increased airflow and power then why waste the money on slipons in the first place instead of going with a full system.
 
I'm still kinda holding out for the (hopefully) release of the 2009 VMax, as I just can't seem to let that thing go....it's just too cool and I want to trade my current stock bike in on it.

I figured that a bike is worth more to a dealer when it's totally stock for a trade-in, than to have a bunch of aftermarket parts hanging all over it, so that's why I only want to mod my current bike "a little bit" with parts that are easy to remove.

I just *really* hope that Yamaha doesn't let me down....

-john
 
Have you considered suppertapps?? these are dual slipons
If you liked thekerker 4-1 loudness you maybe dissappointed in the kerker slipons. They are pretty quite.
there was a posting here a while back inquiring about kerker vs trapps. mosy evryone thought the traps sounded much better. And the trapps are tunable with thier disc system.
 
There is not a system out there that makes the fuel lean out if you don't change the air intake system. These carbs work in a completely different manner then most are used to.

The cobra's are the absolutely worst we have ever tested for HP. They do not have any scavaging ability which is what hurts them the most. They do look cool but suck for power.

There is not a slip-on out there either that we have found to give any kind of noticeable increase. They do give a good weight loss which makes the bike conversly faster.

Having said that.

I do have a pair of kerker slip-ons that I took on trade if you wanted a set of those. These are not in great shape but would be excellent to use to make custom mufflers with (which we can do too). If you did like the slip-ons you could get two of the comp baffles and it would sound very good.

Sean Morley
 
mnmax~
I've looked at the SuperTrapp Systems and I had that system on a 1985 Honda 200x I had when I was high school. It did sound good, but since they diffuse the exhaust in a radial pattern, everything that was within 6" of the outlet was always covered in a black carbon film. On an ATV like that it didn't matter much, plus I was a kid that didn't mind cleaning the thing all the time, but I wouldn't want to have to deal with that with this bike. They are very good systems though other than that, I agree. :)

Sean~
Thank you for the offer, but I think I'll just buy some new chrome plated Kerker slip-on's instead- I like new stuff. :clapping:
Also, when I was in college and had a full Kerker exhaust on my 1985 Max (it was loud) I liked the loudness of the pipes, because hey, I was a young guy that thought "the louder the better"!! Not anymore... Now, I could care less about that crap and I just want something other than stock for looks, but make a little better sound with them too like the Kerker slip-on's do from your report. As I get older, quiet but strong is good... :stickyman:

Thanks again guys, you've really given me some good info that I can really chomp on. :cheers:

I'll post a picture and sound clip of them after I get them on. :)


-john
 
let me know if you get them. I am a kerker dealer and can order them too. It was my understanding they were discontinued.

Sean
 
let me know if you get them. I am a kerker dealer and can order them too. It was my understanding they were discontinued.

Sean
I just saw them on their website.$600 and some dollars!:th_image003::th_signs60:???????????:hmmm:
 
Sean,
What are you asking for those Kerkers? My Vance and Hines are almost played out. Hell, they're twenty years old and parts have been discontinued. I'm tired of welding up parts to keep these things together.
 
Well, the ones I have are old as hell. Took off an 85 and probably on there since 85. Both cans are dinged up - one on the inside where it's not readily seen and the other on the outside. I reskined the really bad one and need to finish welding up the holes from re-attaching. I was going to have them powdercoated when I was done. I think I changed my mind though and decided I could weld flanges where the muffler cans attach and hook up some of my newer carbon fiber mufflers.

I'd like to get $100 out of the pair as they are. They will need to be stripped and coated too which I can also have done.

Sean Morley
 
A friend gave me some kerker slipons for my max and I have a love/hate with them. I really like the sound but it leaves my ears ringing after a long ride. I don't like the looks that much so I'm on the fence about switching back to my stock pipes.
 
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