Author Topic: Silencer to collector box gasket.  (Read 2407 times)

Offline Dolomite_

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Silencer to collector box gasket.
« on: June 23, 2024, 01:28:56 PM »
I have fitted my new downpipe and collector box from Davidsilverspares and also tried using an OEM honda collector box to silencer graphite gasket but the collector box outlet seems to be too big and the gasket starts to break up when its being pushed on.

There is a decent sized gap between the OEM style silencer and collector box outlet so I cant really tighten it until its closed. Has anyone had luck with a different sized gasket? Or used something else as a gasket?

Offline Laverda Dave

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Re: Silencer to collector box gasket.
« Reply #1 on: June 23, 2024, 03:36:24 PM »
There are two sizes of gasket, one (smaller) size is the the downpipe to collector box gasket, there are two of these whilst the other slightly larger gasket fits between the silencer and collector box. Have you fitted the correct size as normally they are a good fit wthout too much crushing. I fit them onto the collector box first and then slide the silencer over, its fiddly but usually goes on OK.
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Offline Dolomite_

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Re: Silencer to collector box gasket.
« Reply #2 on: June 23, 2024, 03:48:24 PM »
Yeah, its definitely the bigger one as it came in a different packaging and part number compared to the 2 smaller ones. I'll try and push it on again. It seemed to be stretching it when I only got it on about 10mm.

Offline Eldrick

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Re: Silencer to collector box gasket.
« Reply #3 on: June 23, 2024, 04:15:57 PM »
I have the same issue with the Brituro silencer, I had to widen the end of it to make the gasket fit in and even then it has deformed the gasket.
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Offline Dolomite_

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Re: Silencer to collector box gasket.
« Reply #4 on: June 23, 2024, 04:20:02 PM »
I have the same issue with the Brituro silencer, I had to widen the end of it to make the gasket fit in and even then it has deformed the gasket.
Did you manage to get in on properly without it splitting?

Offline Eldrick

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Re: Silencer to collector box gasket.
« Reply #5 on: June 24, 2024, 09:56:36 AM »
I have the same issue with the Brituro silencer, I had to widen the end of it to make the gasket fit in and even then it has deformed the gasket.
Did you manage to get in on properly without it splitting?
Not yet, I have to put the cylinderblock and rocker cover back on the bike first.
1975 Honda CB400f - Red

Offline Nurse Julie

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Re: Silencer to collector box gasket.
« Reply #6 on: June 24, 2024, 11:33:40 AM »
I shaved the gasket down with a few razor blade to make it fit.
LINK TO MY EBAY PAGE. As many of you know already, I give discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

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Offline Eldrick

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Re: Silencer to collector box gasket.
« Reply #7 on: June 24, 2024, 07:10:34 PM »
I'm politley asking DS about this and referencing this thread. Maybe it is something that needs attention in manufacturing.
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Offline Nurse Julie

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Re: Silencer to collector box gasket.
« Reply #8 on: June 24, 2024, 07:24:35 PM »
I'm politley asking DS about this and referencing this thread. Maybe it is something that needs attention in manufacturing.
I think DS has been told about this numerous times but the reply was along the lines of 'oh well, never mind' 🙄🙄🙄🙄
LINK TO MY EBAY PAGE. As many of you know already, I give discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline Eldrick

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Re: Silencer to collector box gasket.
« Reply #9 on: June 24, 2024, 08:42:06 PM »
I'm politley asking DS about this and referencing this thread. Maybe it is something that needs attention in manufacturing.
I think DS has been told about this numerous times but the reply was along the lines of 'oh well, never mind' 🙄🙄🙄🙄
Then maybe my wallet will mind next time I need parts...
1975 Honda CB400f - Red

Offline Dolomite_

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Re: Silencer to collector box gasket.
« Reply #10 on: June 24, 2024, 08:44:14 PM »
I shaved the gasket down with a few razor blade to make it fit.

I was thinking of cutting it in half but then there would be a gap. I didn't even think about shaving about a 1mm from the inside, I shall try that.

Offline Dolomite_

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Re: Silencer to collector box gasket.
« Reply #11 on: June 25, 2024, 08:44:54 PM »
So I shaved down the side and it went on easier. But then it the brituro silencer wouldn't fit on, so I shaved the outside down and it still wont fit on. When applying some pressure the gasket just starts to crump up.

I guess I'll have to find a thinner gasket or a roll or a different material.

Offline Dolomite_

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Re: Silencer to collector box gasket.
« Reply #12 on: June 26, 2024, 03:06:16 PM »
So I shaved it down and ended up using a grinder to shave it down further because of the metal wires inside the graphite gasket but it just falls apart once you try to push it on.

It would either fit in the silencer and then not onto the collector box or visa versa.

I might need to make my own gasket out of something. Has anyone used other exhaust gasket materials?

Offline Skoti

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Re: Silencer to collector box gasket.
« Reply #13 on: June 27, 2024, 07:58:41 AM »
So I shaved it down and ended up using a grinder to shave it down further because of the metal wires inside the graphite gasket but it just falls apart once you try to push it on.

It would either fit in the silencer and then not onto the collector box or visa versa.

I might need to make my own gasket out of something. Has anyone used other exhaust gasket materials?

You could try Hi Level for a collector box seal, they list various sizes on their website here:-

https://hilevel1.co.uk/pc_combined_results.asp?search_cat=searchexact~pcpcm.parent_pc_id~A6397370794B48ACA035DAFD5CED10F1&pc_id=A6397370794B48ACA035DAFD5CED10F1

Although they normally only supply the trade, so you may have to order via your local bike shop.



Hope this helps. 
Skoti


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