snap, crackle & pop

[cookie]

or how i spent my saturday: trying to stop the ever increasing overun backfires on the on my 1150.

i found the Y piece to down pipes connections blowing rather badly a while back and fixed that at the time, i was rather disappointed it made sod all difference to the backfiring.

on saturday i stripped the whole fecking system off and refitted it from the manifolds backwards using lashings of silicone + some carefully cut bits of beer tin to span the slots in the female joints. these ally bits also help the clamps to tighten right down, the crossover pipe in particular would not tighten enough on it's own

i was pleased to see a blow mark on that joint, so that could be the cause. nice to have found some real evidence anyway. that joint has very little overlap & needs special attention on assembly IMO.

i left the bike overnight for the silicone to go off, warmed it up in the garage so i could see if it still backfired while revved in neutral. it did, in spectacular,flame belching style. it never shot flames before

i then went out in the pissing rain for a test ride. very pleased to note that backfires were now entirely absent. after about 30 miles, i was getting the odd backfire while changing gear again, not so much while slowing down as before.

by the time i got home, it was about 50% as bad as it was before i did any work. so today, i've taken the whole downpipe section off & redone it, paying extra special attention to the crossover joint even though there was no sign of a leak this time. if left to it's own devices during assembly, it tends to "fall open" a bit. squeezing it up gets a couple more mil of overlap.

a question though: do all remus Y pieces run so close ( it's wearing the ally away) to the gearbox on the r/h/s?

i still think it's going to leak AGAIN when i use it a bit, but i did have one success i'm rather pleased with. while system was off, i ground off those fecking hideous brackets on the Y piece that mount the crappy heat guard that fell off months ago

 

[Sergeant Pluck]

Yup - mine run very close. Tried loads of times now with 2 different bikes, two different y-pieces and two different cans . I have never been able to push the ends of the y-piece far enough over the downpipes to completely clear the u-shaped clamping slits* in the y-piece -- I always end up with small blow marks... I've put this down to poor manufacturing on the part of Remus and was toying with the idea of getting a second-hand set of downpipes next year and having a y-piece welded on! I'd be interested to hear if you manage to get these gaps closed. I use a carefully snipped bake-bean can in between the y-piece and end can as well - usually ends up with me slicing me feckin fingers off but does help getting a better fit.

*I don't even attach the y-piece to the centre-stand hangers with the two long torx bolts - I push the whole assembly further forward than this.

 

[Den]

Why do we accept these badly made HUGELY expensive products. If they are sold to fit a specific model,THEY SHOULD FIT. We shouldnt have to piss around with sliced beer tins.

 

[MasterDabber]

Every time I start to think about changing from the OEM pipe/cat I see a thread like this and think... is it worth the hassle?

 

[retroman]

Every time I start to think about changing from the OEM pipe/cat I see a thread like this and think... is it worth the hassle?

Don't bother.

I'm a recent convert back to OE ... Remus=rubbish

 

[cookie]

to be fair to remus,

in my case it is the OEM bmw downpipes that are proving hardest to seal.

to each other

 

[Keith Chapman]

a question though: do all remus Y pieces run so close ( it's wearing the ally away) to the gearbox on the r/h/s?

Cookie, my Y piece clears the r/h/s gearbox by at least 1cm. has your down pipe been bent so that it sits on the skew??

 

[cookie]

Cookie, my Y piece clears the r/h/s gearbox by at least 1cm. has your down pipe been bent so that it sits on the skew??

nope, all looks factory & there is no way to adjust it for fit.

it's worn a little ally away where the bolt passes through. won't do any harm as far as i can tell., just sloppy engineering from remus by the looks of it.

so yours misses by 1cm, mine touches & sgt plucks won't even pull up on the downpipes properly. i'm impressed

 

[pomm001]

left the bike overnight for the silicone to go off

Cookie
your wasting your time and money with Silicone RTV ( Room temperture vulcanising) on your exhaust sytem,dependant on grade
it will only go to 200 C ish.
Try something like 'firegum'
My adventure has a Y piece with standard can and although I can make it 'pop' on the overun, its not too bad.
I have adjusted my riding technique with this in mind, ie not snapping the throttle shut too quickly etc.
I dont think you can ever totally get rid of it without putting the CAT back on.
Dont let it get you down !

 

[cookie]

it certainly appeared to not hold up too well to testing. i'd been told it was good to 400c, must have been misinformed. i've used it in the past with success.

if today's new attempt doesn't work, i'll switch to firegum or similar. though i always find it goes hard & falls out if pipes flex. maybe i'm thinking of that chalky white stuff? anyway, it won't take long to redo, i'm getting good at it

meanwhile, somebody ought to tell these people about silicone's limitations

doesn't really get me down. besides, i'd take the snap crackle & pop over the standard hoover noise anyday, but don't quote me on that when i change back
i'm a way into this and there's no going back, but i can say i'd never bother fitting another system from scratch.

let's see:

Y piece & can £390: not quite that bad as Y piece came with the bike & the can came s/h but still bucks.

techlusion: £130 but i got my money back 'cos it didn't work properly. WEEKS wasted there*

BB powerchip: £250ish IIRC and believe me, i'm trying not to

endless faffing about: priceless: lucky i'm not charging myself

still, i console myself, it sounds way nicer than stock in a funny WW1 biplane kind of way. it's not a duke on termis, that's for sure

*don't want to put folks off the one that's for sale in the FSAW forum. i believe they usually work, but can catagorically state, and techlusion USA agreed, it doesn't work fully on mine.

while i'm on a roll here, i'd like to mention the last aftermarket system i bought, that wasn't for a guzzi (they work with anything).

a yoshi 4-1 for a GS1000. pile of shit. took weeks to jet, mostly 'cos it took me a while + many high speed plug chops to suss that the outer cylinders ran weaker than the centre two. by the time it was right the baffle rusted out

time for my pills now

 

[pomm001]

Cookie

If you were told that RTV is good for exhaust joints then you were misinformed
An automotive grade of RTV 5900 ( Loctite) is good to about 250, will tolerate the odd spike to 300 deg. C
and this is the dog’s danglies of RTV used by all of the big motor manufactures.
Automotive RTV should not smell like vinegar when it comes out of the tube, if it does use it on your sink or fish tank, its cheap tack
Automotive products have different recipe, both rely on the moisture within the atmosphere to cure

 

[cookie]

what temperature do you think the crossover pipe joint on my 1150 reaches?