Info about Supertrapp KZ750 Header

I measured the primary tubes on the pipe I have on the outside bends at 21" (to the collector) which is a lot shorter than a typical Kerker or V&H street pipe.

A pic of my 650 from 1986 with a V&H pipe, notice the long primarys and long collector. That pipe is basically a copy of the earlier RC pipe.

 


 

Injected wrote:

I measured the primary tubes on the pipe I have on the outside bends at 21" (to the collector) which is a lot shorter than a typical Kerker or V&H street pipe.

A pic of my 650 from 1986 with a V&H pipe, notice the long primarys and long collector. That pipe is basically a copy of the earlier RC pipe.

 

 

Thanks for the leg work and advice on this exhaust system.  You have convinced me that this system is indeed a race system, which frankly, is not what I need for my bike.  Guess I got lured in by the stainless Supertrapp unicorn business.  Ha ha.  

Back when rebuilding my bike, I found a great price on a 800cc kit, so the plan was to slam that in.  On further review, the cylinder bores were in decent shape, and I frankly, don't need tons of power, so the decision was made to stay stock.  There is real beauty in a full stock bike, from the standpoint of not needing to question things like carb jetting!  

I'm still going to stay the course of cleaning and refurbishing this pipe.  I'll trial fit, but if the center stand is blocked, that will most likely mean it doesn't stay on the bike.  

Came across this header on ebay a while back.  It's apparently from Germany.  Based on the collector, it seems closer to what I want for my bike; it should tuck up close under the sump.  Anyway, it's all good.  The search continues...

 

I believe that pipe you bought will be just fine even on a stock engine.

When I mentioned "race system", I meant it would probably be most "efficient" at higher RPM's and probably not make as much torque as a longer tube street orientated pipe. Would you be able to notice the difference? probably not enough to tell on the seat. Were only talking about a very small difference in HP and torque between the two types of pipes.

Its the combination of bigger CC engine, more CFM cylinder head, higher lift cams, and bigger carbs where pipes like that actually push you back in the seat.

If you are running a stock air box the jetting will most likely not have to be altered.

That pipe probably rocks at +7000 RPM +100 MPH

Injected wrote:

I believe that pipe you bought will be just fine even on a stock engine.

When I mentioned "race system", I meant it would probably be most "efficient" at higher RPM's and probably not make as much torque as a longer tube street orientated pipe. Would you be able to notice the difference? probably not enough to tell on the seat. Were only talking about a very small difference in HP and torque between the two types of pipes.

Its the combination of bigger CC engine, more CFM cylinder head, higher lift cams, and bigger carbs where pipes like that actually push you back in the seat.

If you are running a stock air box the jetting will most likely not have to be altered.

That pipe probably rocks at +7000 RPM +100 MPH

Thanks for the encouragement!

Like you, I presume, based on all your 650/750 type bikes, I just love the balance of power to weight to handling, that the 650/750 provides.  I sold my GS1000S after riding my 750, because I much prefer the lighter feeling and there was plenty of power for me.  

Most of the dyno charts I've seen for different headers show just minor improvements, if any, other than some that are very loud, for the bigger bikes.  If this one fits the way I like, I'll run it, even if it's not optimum for my use case.  I doubt I'll lose enough power to even notice, the way I ride.  Just gotta get off my butt, and check fitment.  Tomorrow maybe?  I don't even mind trying to make a new mid-pipe, if that's what it takes to clear the center stand.  Hope it doesn't come to that, though.

Yes, most of my practical knowledge is on the 650/750 models as I have never owned anything bigger. I also prefer the mid sized bikes as they always fit me better, have ridden plenty of bigger bikes but never felt as connected to them as my old 650.

My 750 is completely stock except for the CVK34 carbs and it has plenty of power.

The biggest performance improvements a 4 into 1 pipe can make is ground clearance and weight reduction.