exhaust leak right at header

[bluesbreaker45]

Hello all!

I have a 1994 FZR 1000 that has a terrible exhaust leak right where the header bolts to the motor, I believe. The bike had been fitted with a full Hindle exhaust long before I bought it and the exhaust leaked then. I thought it was a simple repair- change the exhaust gaskets. but I have installed new exhaust gaskets twice now with no luck.
The leaking "sound" seems to stop between 3300 and 4000 rpm???
Is there a trick to installing the exhaust gaskets on the 1000 motor? I think followed procedure when re-installing the header (proper torque, proper order).

Do you guys have any advice?

Thanks,
Zack

[sweekster]

As far as swapping the gaskets you're doing it right. The gaskets? Where are you getting them from? Dealer? I can only think of a warped flange on the header itself or a bent stud if it's not the gaskets.

[haro504]

if it leaked when the exhaust was put on it might not fit that engine right ( to much of an angle between the header and engine mating surfaces) is it just one cyilinder or all of them

[cecorri]

Are you sure its an exhaust leak ? I have found that exhaust leak on bikes to be very rare, especially on mid 80's and newer... could it be motor noise ?

[mossy1200]

Are you sure its an exhaust leak ? I have found that exhaust leak on bikes to be very rare, especially on mid 80's and newer... could it be motor noise ?

If you get a mate to hold hand over tail pipe you will tell where its coming from by puffing talc powder at the headers joint.
It sounds like the angle of pipe is wrong on the headers.Is it possible they are not fzr headers?
Have you tried bolting them up without any other exaust mounts connected?This will tell you if the angles not correct.

[bluesbreaker45]

Thanks for the replies everyone.

The gaskets were bought from a dealer (bike bandit actually through here)

I am certain it is an exhaust leak(sometimes on start-up I can see a little exhaust make it's way up past the handle bars)It seems the inner two header pipes are the ones leaking -when I changed exhaust gaskets the second time I noticed the two outside gaskets had no black soot on them.

I have considered that the header wasn't made for an FZR1000. but without the slip-on portion of the exhaust on, everything seems to line up fine. Is there a way to verify if the header was made for an FZR 1000?

I have also thought it to be, at least in part, motor noise and I will see after I remedy the exhaust leak.

I believe I will try the powder technique to pinpoint the exact leak location.

Thanks guys,
Zack

[bluesbreaker45]

So it turns out that the gaskets were sealing great. The Hindle header has these coupling pieces that bolt to the head and then hold the exhaust on with a spring on each pipewhich were leaking.

So I fix that and now it's leaking at the gaskets. I am so tired with this exhaust leak business. Is the trouble I'm having typical of after-market exhaust systems??

Thanks again guys,

Zack

[yamaha_george]

So it turns out that the gaskets were sealing great. The Hindle header has these coupling pieces that bolt to the head and then hold the exhaust on with a spring on each pipewhich were leaking.

So I fix that and now it's leaking at the gaskets. I am so tired with this exhaust leak business. Is the trouble I'm having typical of after-market exhaust systems??

Thanks again guys,

Zack

Zack,
On an FZR I have not had this but similar problem with 2 stroke race exhausts with the stubs and spring assembly by the exhaust port.

What was recommended was to open the stub a tad with a big socket. once the stub is bolted in place on the engine, smear RTV ( a silicon sealant ) on both the stubb and the pipe, clip the spings in place, bolt up the rest of the mid pipe / slip on etc . Leave for 24 hours to set.

I must admit I was dubious about using silicon glue so close to the exhaust port figuring the heat of the gases coming out but I did not have any more power sapping leaks.

The downside is dismantling & clean up but on a Big four stroke the need to do that is greatly reduced.

[bluesbreaker45]

Thank you very kindly Yamaha George. I will be trying this but I'm a little confused about what you mean by "open up the stub with a big socket". do you mean open up the end that goes into the head or open up the end that goes into the pipe? Also, around here at least, there are several varieties of RTV silicone. Should I just get the one with the highest temp rating?

I do thank everyone for their input and advice,

Zack

[reelrazor]

For those slip-joint spigots with springs to retain the pipe, the best thing I have found is to use "exhaust tape"

http://www.denniskirk.com/jsp/product_c ... Id=&mmyId=

It's semi-pricey, but you stretch it and wrap the male end of the pipe to seal in teh female. I used to always get it under the PJ1 brand-but I am not seeing that anywhere online....

Mount the spigots to the head, but don't torque them.....install the pipe with exhaust tape and springs (and rear hanger), then torque spigot bolts. You leakage should be gone.

[yamaha_george]

Thank you very kindly Yamaha George. I will be trying this but I'm a little confused about what you mean by "open up the stub with a big socket". do you mean open up the end that goes into the head or open up the end that goes into the pipe? Also, around here at least, there are several varieties of RTV silicone. Should I just get the one with the highest temp rating?

I do thank everyone for their input and advice,

Zack

Zack,

I am assuming here that the pipe slips into the stub NOT the stub into the pipe,



The leak is caused by the stub (the bit that is bolted to the engine) NOT aligning with the actual pipe itself.
since both are round but the center lines do not align it is easier to make the stub diameter a little bigger to allow some play in the joint to get a better alignment and use the highest temperature RTV you can get to seal the rest (or use RR's method which I have never seen BUT RR is pretty on the ball as he still does a lot of that kind of thing )



If it is the stub into the pipe you open up the pipe with the socket to get the required play & seal with RTV or RR's stuff..

HTH
Y-G