Yoshimura oil cooled header!

[posplayr]

A little Giablo R&D!!! Okay friends, this is the deal! The Yoshimura header fits the head. No clearance issues. You MUST alter the flanges! Even the muffler fit, since I have already modified my frame with custom rear-sets. BUT the bend on the down tubes is incorrect. There are actually two bends. Way too much space between the bottom of the engine and the collector. I could have dealt with that, but it looked wrong. So, who wants an almost new Yosh exhaust for their 2nd generation GSXR1100?

Without pictures it is hard to comment; but here is a picture of a 2nd gen GSXR 1100 Yoshi 4:2:1 pipe that is hanging low because it is hitting the cross pipe. I solved the problem with spigots to extend the pipe 0.75".
I now have approx 1/2" clearance between the pipe and the oil pan.

http://www.thegsresources.com/_forum/showpost.php?p=1027130&postcount=55

Another potential solution would be to have some aluminum cylindrical spacers made that would be captured inside the exhaust port (OEM gasket on both sides) and space the header out 3/4" net. U would still use the header's flanges, but with longer bolts.

[El Giablo]

Thanks for the comments. The header is similar to the one on your GSXR. The link for the pipe bender is not working. I can take pictures today if interested. Also, there is a part number on the exhaust. Maybe I can find a diagram online. I probably will not alter the exhaust any further. I have a line on a '87 GSXR with a 1200cc engine.

[tone]

Ok here is the post where i eat humble pie

Let me explain further, my mate turned up on his gsx11 today as i was in the middle of doing something involving heavy engines & a bad back so as i was busy i only had a quick look at his bike but it seemed that jim is correct & the mounting flange holes on these are a couple of mm further apart than on the b12 or the gsx750 (60/62mm ish)

Once i'd finished what i was doing it started to bug me as i KNOW my b12 exhaust had been on both bikes so i decided to investigate more It seems that the holes in the flanges on my exhaust had been filed out to suit the 1100 engine by a previous owner & i had not realised or more likely never looked

I appologise unreservedly for my previous incorrect posts on this matter

Normal service will be resumed soon, tone

[Billy Ricks]

I might be wrong but I believe port diameter is different on the GSXR based engines and everything but the '83 and up 700/750E models. I had picked up a GS1100 V&H pipe but the pipe diameter was too large for my ports. Does the GSXR based pipes have slop inside the port? The GSXR based stuff is the same as my 700.

[Speedo]

Forgive my facetious digression on this (obviously very serious to you guys) issue, but I just thought the thread title to be hilarious. I was surfing site, saw the title, and just HAD to read string thinking to myself: "wow, an 'oil-cooled header' eh?....I wonder how the hell they built that and make it work? A double wall header pipe with an oil divert line to it from engine to 'cool' it" and "I know that exhaust gas temp is pretty much hottest thing going on - 1200degF or so - but why on earth would the exhaust need to be 'cooled'?".

In all seriousness, it's an interesting thread and quite typical of "making stuff work" in a whole bunch of applications besides exhaust on old bikes (and cars, tractors, toasters, etc, etc).

[posplayr]

I might be wrong but I believe port diameter is different on the GSXR based engines and everything but the '83 and up 700/750E models. I had picked up a GS1100 V&H pipe but the pipe diameter was too large for my ports. Does the GSXR based pipes have slop inside the port? The GSXR based stuff is the same as my 700.

Billy,
The simple answer is that the port sizes must be close enough (maybe no more than 2-3 mm diameter difference).

My Yoshi 2nd Gen GSXR1100 4:2:1 fits nicely inside the GS1100E as did my Muzzy 4:1 from 1st Gen GSXR1100G (86).

As mentioned it is the flange bolt hole spacing that is smaller on the GSXR with the required modification of replacement of the flanges. Tone's B12 flanges were slotted (as mine were done in that picture) so the pipe can go back and forth between GS and GSXR.

From the measurements on both my 2nd gen 4:2:1 pipe as well as the 1st gen 4:1 pipe if you get the flanges properly configured so that the pipe can bolt up without intereference with the frame, the depth under the belly is not excessive and should work well. The GSXR750 motors have a shorter stroke and probably would not fit the GS1100.

Jim

[posplayr]

Ok here is the post where i eat humble pie

Let me explain further, my mate turned up on his gsx11 today as i was in the middle of doing something involving heavy engines & a bad back so as i was busy i only had a quick look at his bike but it seemed that jim is correct & the mounting flange holes on these are a couple of mm further apart than on the b12 or the gsx750 (60/62mm ish)

Once i'd finished what i was doing it started to bug me as i KNOW my b12 exhaust had been on both bikes so i decided to investigate more It seems that the holes in the flanges on my exhaust had been filed out to suit the 1100 engine by a previous owner & i had not realised or more likely never looked

I appologise unreservedly for my previous incorrect posts on this matter

Normal service will be resumed soon, tone

You are only providing a free service; Sometimes the memory fails whereas the hand would have been more deadly accurate.

We are glad for your years of experience and willingness to share it.