Freeplay in downpipes due to oversized rings

[RempageR1]

Hi,

I`ve got a strange problem with my Vmax with which I hope you guys can help me.
Since my rear downpipes were loose, with the clamp fully tightened (7 in drawing below) you could still slide them out of the clamp leaving the ring (5) and stopper (6) in place. The downpipes were only held in place by the exhaust covers. What I did was order new gasket rings (number 5 in the picture below). So far, so good.

However, when I tried to fit them, they would just slide over the downpipes although they should be a tight fit. The old gasket rings however would still grip the downpipes, but only just (that`s why I ordered replacements). So it seemed the worn old rings still had a smaller inner diameter then the new ones.
After going back to the dealer where I bought them they checked this with Yamaha. The answer I got from them is the following: Ring 6 on the drawing above should have a small gap in it (sawed through on on side). An example is a drawing form a 2008 R6:

My ring 6 should look like ring 5 on the second drawing they claim...

I highly doubt this but could someone comfirm they are wrong? The copper rings sould fit snug on the downpipes right? and they should keep them in place?

Some help on this matter please

 

[SpecOps13]

I looked here.. http://www.yamahapartshouse.com/yamaha-parts.aspx?aribrand=YAM#AssemblyPartsSearch|model_kpf*jTkEj1E2RQYkjvAPIQ==|assembly_2oEy7kBITq3sQMcD3Zk2Ig==|brand_pRpGfG8SWOclHVggGtWxpg====

3 pictures I just took of my old exhaust system may help you. There are no "Cuts" in the gaskets and once the clamp is tight.. The exhaust system is tight and sealed...

Good Luck,
Dave in FLorida

 

[one2dmax]

A heavily worn ring will let the pipes rattle.

Sean

 

[RempageR1]

I looked here.. http://www.yamahapartshouse.com/yamaha-parts.aspx?aribrand=YAM#AssemblyPartsSearch|model_kpf*jTkEj1E2RQYkjvAPIQ==|assembly_2oEy7kBITq3sQMcD3Zk2Ig==|brand_pRpGfG8SWOclHVggGtWxpg====

3 pictures I just took of my old exhaust system may help you. There are no "Cuts" in the gaskets and once the clamp is tight.. The exhaust system is tight and sealed...

Good Luck,
Dave in FLorida

Thank you! I knew I wasn't crazy...

The copper rings do fit snug around the downpipes right? They are hard to remove from the downpipes?

Can anyone give me an exact reading of the outside diameter of the downpipes where the copper ring is seated as well as the inner diameter of a copper ring (preferably a new one). Thanks again!

 

[SpecOps13]

The copper ring is a tight fit on the pipe. I don't have new ones but I would guess they start out only a few thousandths larger than the pipe. The copper is compressed when the clamp is attached and likely become tighter with heat cycles of the exhaust.. Your exhaust size is not going to be any different than mine. I can't measure it right now.. When I can, do you need MM or Thousandths????

 

[RempageR1]

The copper ring is a tight fit on the pipe. I don't have new ones but I would guess they start out only a few thousandths larger than the pipe. The copper is compressed when the clamp is attached and likely become tighter with heat cycles of the exhaust.. Your exhaust size is not going to be any different than mine. I can't measure it right now.. When I can, do you need MM or Thousandths????

Hi,

Thank you for your reply. I`ve tried to see if I could compress the ring by tightening the clamp to the specified torque but that didn't work. I haven't tried to see what happens when the pipes get warm, that could indeed make the rings compress easier.

If you could, MM would be fine.

Thank you!

 

[SpecOps13]

My copper ring is on so tight, it won't be reasonable to take it off. Best measurement I get is 34.85 MM. The copper ring does not fit perfectly square so that may be slightly off.. This is with my calipers against the forward edge of the copper gasket, over the pipe.... It will not move without destroying it...

Dave In Florida

 

[RempageR1]

My copper ring is on so tight, it won't be reasonable to take it off. Best measurement I get is 34.85 MM. The copper ring does not fit perfectly square so that may be slightly off.. This is with my calipers against the forward edge of the copper gasket, over the pipe.... It will not move without destroying it...

Dave In Florida

Hi Dave,

Thank you so much for measuring them for me. The rings I got have an inside diameter of 35.15mm inside diameter. So it seems they would just fall off of your downpipes as well :rofl_200:

Has anyone replaced these rings on their bike? Did they go on tight or are they supposed to shrink when going through a heat cycle?

Thanks all!

 

[SpecOps13]

It will take someone more knowledgeable than me to help you further...

Hope I have you aimed in the right direction to solve this problem..

You might try messaging Sean Morley (one2dmax) he posted above or
go to his forum here and make a thread for help....

Good Luck,
Dave

 

[one2dmax]

The rings are normally a snug fit and not easily taken off/on a used pipe. maybe a new pipe and ring would slide easily?

Sean

 

[RempageR1]

That leaves me with just one option to try: Install the new rings and see what happens when I heat them up (when riding). Maybe they will shrink due to the pressure from the clamps and the heat so they do fit snug. Thanks all for helping on this one!