Date: 26-10-25  Time: 21:47 pm

Author Topic: Black silicone on cracked inlet rubbers  (Read 4612 times)

sc0ttie

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Black silicone on cracked inlet rubbers
« on: 06 June 2015, 12:18:05 pm »
My inlet rubbers have some cracking around them, although they seem to be just surface cracks for now and the bike is not running badly or anything. The cracks have been there a while though and I was just wondering if it would be worthwhile filling them with a little black silicone filler, the high temp kind as a preventative measure?


I have some of that silicone already so I could do that today if it would help slow down the cracking going deeper. If it is worth doing it, would it be best to do it after engine is warmed or on a cold engine? Thinking about heat and expansion of materials etc.

darrsi

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Re: Black silicone on cracked inlet rubbers
« Reply #1 on: 06 June 2015, 12:34:59 pm »
You've got nothing to lose at all by doing that, i would've thought it might be better if the rubbers were warm, but it probably doesn't really matter.

sc0ttie

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Re: Black silicone on cracked inlet rubbers
« Reply #2 on: 06 June 2015, 12:57:32 pm »
You've got nothing to lose at all by doing that, i would've thought it might be better if the rubbers were warm, but it probably doesn't really matter.


Ok thanks, I will smooth some into the cracks tonight then before sun goes down then it has all night to cure.

rambothecat

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Re: Black silicone on cracked inlet rubbers
« Reply #3 on: 19 July 2016, 02:29:46 pm »
Thinking about doing the same thing. How did it go?

fazersharp

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Re: Black silicone on cracked inlet rubbers
« Reply #4 on: 19 July 2016, 05:18:17 pm »
Yep I do that to mine too

Albert Herring

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Re: Black silicone on cracked inlet rubbers
« Reply #5 on: 21 July 2016, 10:07:51 am »
Local shop did this to mine as a cheap fix when it was running rough and not starting last year, seems to have worked.

fazersharp

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Re: Black silicone on cracked inlet rubbers
« Reply #6 on: 21 July 2016, 12:03:28 pm »
Local shop did this to mine as a cheap fix when it was running rough and not starting last year, seems to have worked.
Its very rear that they get so bad that this happens.Or to say they have to be very bad before this happens 

Albert Herring

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Re: Black silicone on cracked inlet rubbers
« Reply #7 on: 21 July 2016, 06:37:48 pm »
Local shop did this to mine as a cheap fix when it was running rough and not starting last year, seems to have worked.
Its very rear that they get so bad that this happens.Or to say they have to be very bad before this happens


My bike is about one step above "barn find". Or at least, it's spent a few winters outside, put it that way.

fazersharp

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Re: Black silicone on cracked inlet rubbers
« Reply #8 on: 21 July 2016, 08:44:22 pm »
Local shop did this to mine as a cheap fix when it was running rough and not starting last year, seems to have worked.
Its very rear that they get so bad that this happens.Or to say they have to be very bad before this happens


My bike is about one step above "barn find". Or at least, it's spent a few winters outside, put it that way.
In that case you will be ok as it is the sunlight that does it

celticdog

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Re: Black silicone on cracked inlet rubbers
« Reply #9 on: 21 July 2016, 09:16:13 pm »
Filling black cracks eh?  :eek  reminds me of my 1st GF, 'twas like a black cat with its throat cut, mind you it was the 80's the ladies where a bit more 'hirsute' back then.

pointer2null

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Re: Black silicone on cracked inlet rubbers
« Reply #10 on: 23 July 2016, 06:27:44 pm »
Most old fazers have got cracked rubbers on the carbs - but these are much thicker than you think. Anyhow, one way to tell if the crack goes all the way through is to spray a little wd40 on the crack. If it gets sucked in then you have a leak, if it runs off (as it most often does with cracked rubbers) then you're fine; it's just surface cracking.

markeb

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Re: Black silicone on cracked inlet rubbers
« Reply #11 on: 23 July 2016, 07:20:15 pm »
I found that back to black works to, was cleaning the bike . have cracked inlets engine raced when spraying back to black on to plastic bits, thought ooh shit! but on checking again was fine. the cleaner was going into air box intake lol , but was looking to try vulcanising solution on my cracks, but black silicone sounds promising.

fazersharp

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Re: Black silicone on cracked inlet rubbers
« Reply #12 on: 23 July 2016, 08:32:10 pm »
I found that back to black works to, was cleaning the bike . have cracked inlets engine raced when spraying back to black on to plastic bits, thought ooh shit! but on checking again was fine. the cleaner was going into air box intake lol , but was looking to try vulcanising solution on my cracks, but black silicone sounds promising.
Back to black = the new nitro

celticdog

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Re: Black silicone on cracked inlet rubbers
« Reply #13 on: 23 July 2016, 11:37:32 pm »

Grib

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Re: Black silicone on cracked inlet rubbers
« Reply #14 on: 30 July 2016, 10:48:34 pm »
http://www.ebay.co.uk/itm/FZS-600-Fazer-5DM7-2000-Carb-Carburettor-to-Head-Rubbers-Pack-of-4-/131167949179?hash=item1e8a38117b:g:V48AAOxyaTxTSDr8


At £70 a set for pattern parts, it's well worth trying the black or clear silicone.


I bought a set of these a few weeks ago from M&P and they are exactly the same brand (Ars) as the originals.

Dave48

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Re: Black silicone on cracked inlet rubbers
« Reply #15 on: 31 July 2016, 05:53:21 am »
http://www.ebay.co.uk/itm/FZS-600-Fazer-5DM7-2000-Carb-Carburettor-to-Head-Rubbers-Pack-of-4-/131167949179?hash=item1e8a38117b:g:V48AAOxyaTxTSDr8


At £70 a set for pattern parts, it's well worth trying the black or clear silicone.


I bought a set of these a few weeks ago from M&P and they are exactly the same brand (Ars) as the originals.



Recently I noticed that the cracks on two of the rubbers were far deeper & extensive than on the other pair. Decided to bite the bullet & ordered a set as above from M&P for £69-99 delivered. The rubber is actually quite thick so worth checking depth of cuts before laying out cash for new ones-the silicone treatment will be fine on light to moderate cracks.
I tried to take the "long view" as was experiencing an unsteady idle & decided to give the carbs a complete overhaul as the bike now 15 years old.
In the end I replaced both air & fuel filters & purchased 4 carburettor overhaul kits, again from M&P @ £9-99 each.
Removing the carbs is not something I would want to do more than necessary as there is limited access.
One thing did help refitting carbs to new rubbers & that was a light application of red rubber grease around the new rubbers & a thin piece of soft wood on the airbox side of carbs to apply gentle even pressure to pop all 4 in simultaneously.
Finally a carb balance & shes running like she should.
Once every 15 years I can cope with!

darrsi

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Re: Black silicone on cracked inlet rubbers
« Reply #16 on: 31 July 2016, 06:23:16 am »
http://www.ebay.co.uk/itm/FZS-600-Fazer-5DM7-2000-Carb-Carburettor-to-Head-Rubbers-Pack-of-4-/131167949179?hash=item1e8a38117b:g:V48AAOxyaTxTSDr8


At £70 a set for pattern parts, it's well worth trying the black or clear silicone.


I bought a set of these a few weeks ago from M&P and they are exactly the same brand (Ars) as the originals.



You bought Ars rubbers to sort out your black cracks.
It's almost likea Carry On film.  :lol

phil mcglassup

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Re: Black silicone on cracked inlet rubbers
« Reply #17 on: 31 July 2016, 10:17:24 am »
I have heard of bike owners, not necessarily Fazer owners, who cut lengths of suitably sized bicycle inner tubes to the same length as the inlet rubbers. The lengths of inner tube then slide onto the outside of the inlet rubbers,  clamp 'em on.....job done !!