Date: 27-10-25  Time: 21:24 pm

Author Topic: Leaky downpipes  (Read 1362 times)

bbb

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Leaky downpipes
« on: 18 May 2014, 02:19:52 pm »
Replaced my rotten pipes with a set of motad Venoms and genuine Yamaha gaskets but cylinder 4 is popping at the head  :'( . Don't want to tighten them any more as I will snap a stud so it looks like all the pipes off and another set of gaskets but can I use a bit off assembly paste?


Spent ages soaking the nuts with Plus Gas so they came off fine then ran a tap through the nuts before I put them back on with plenty of copper grease. Feeling very pleased but the sod started leaking.

His Dudeness

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Re: Leaky downpipes
« Reply #1 on: 18 May 2014, 02:37:36 pm »
Try taking them off and refitting them again. Cylinder 4 probably didn't line up properly. You can reuse the exhaust gaskets there's no need to get new ones

humbucker88

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Re: Leaky downpipes
« Reply #2 on: 18 May 2014, 03:47:56 pm »
If you've recently taken the nuts off then they should be fine to get off again, it's only when they've been left a long time that they're really at risk of snapping the stud. Take them off and refit, if they gaskets are fairly new, reuse them, if they're the original ones then replace as they're fairly cheap anyway.

bandit

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Re: Leaky downpipes
« Reply #3 on: 18 May 2014, 05:49:27 pm »
Don,t forget the bike will need to have it,s carbs balanced after fitting new downpipes. :) 

Buzz

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Re: Leaky downpipes
« Reply #4 on: 19 May 2014, 09:22:08 am »
You could get some nice Brass domed nuts for £6, it'll stop the crap getting in and they also look nice as well.  The only thing you might find (as I did) was that a few of them were too short and needed a washer.


http://www.ebay.co.uk/itm/M6-Brass-Dome-Nuts-Pack-of-10-FREE-1st-CLASS-UK-POST-/121326538246?pt=LH_DefaultDomain_3&hash=item1c3fa00e06

bbb

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Re: Leaky downpipes
« Reply #5 on: 23 May 2014, 06:05:15 pm »
Got the pipes off and have cleaned all the carbon blow-by off the new gaskets ready to re-assemble when it stops raining. Does it matter which way round the gaskets go in? They have a flat face and a slightly rounded face, does the flatter side go to the engine?


MoT tomorrow so a bit of a rush job.




Thanks


His Dudeness

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Re: Leaky downpipes
« Reply #6 on: 23 May 2014, 07:50:08 pm »
Don't think it matters which way they go. A dab of grease can help keep them in position when you're fitting the exhaust.

bbb

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Re: Leaky downpipes
« Reply #7 on: 23 May 2014, 09:34:31 pm »
Re-assembled after cleaning the exhaust ports with wet and dry but still blowing.


Dis-assembled and ashamed as I am to admit it a smear of Fire Gum on the faces of the downpipes has stopped it blowing. Would seem the downpipe on cylinder 4 wasn't fully mating with the gasket.