skinned knuckles

[easy now andy]

inspired by the wrench monkeys





if i ever have to do this again...i'm taking the exhaust off the bike.

[protoborg]

What does it do?

[easy now andy]

Originally Posted by protoborg

What does it do?

supposedly cuts down thermal loss from the headers by 50%...and looks cool as fuck.

[protoborg]

Originally Posted by easy now andy

supposedly cuts down thermal loss from the headers by 50%...and looks cool as fuck.

You got a cattylitic fartbox on there?

[easy now andy]

Originally Posted by protoborg

You got a cattylitic fartbox on there?

on a '96 air cooled ducati? nope. not even got baffles...

[Weeksy]

Sorry, i think it's a complete monstrosity and always have on 99% of bikes. I've seen the odd Exile bike it looks slightly less of a disgrace on... however very very rare.

[easy now andy]

Originally Posted by Weeksy

Sorry, i think it's a complete monstrosity and always have on 99% of bikes. I've seen the odd Exile bike it looks slightly less of a disgrace on... however very very rare.

i bet your loving the state of my sump aren't you?

[protoborg]

Originally Posted by easy now andy

on a '96 air cooled ducati? nope. not even got baffles...

I would see it as a backward step for 2 reasons:-

1/. Added to the mass of the bike with no measurable advantage.
2/. If you have a stainless zorst this will cause the metal to run hotter which promotes crystal growth in the metal, and the stainless becomes brittle

[easy now andy]

Originally Posted by protoborg

I would see it as a backward step for 2 reasons:-

1/. Added to the mass of the bike with no measurable advantage.

2/. If you have a stainless zorst this will cause the metal to run hotter which promotes crystal growth in the metal, and the stainless becomes brittle

1/ hot gasses move quicker, so there is your advantage. as for added weight, really that's not a concern for me.

2/ mine is mild steel, and i reckon you're talking bollocks. petrol exhaust gas temperatures are what? about 700c? an austenitic stainless such as 308 or 316 copes fine.

[protoborg]

Originally Posted by easy now andy

1/ hot gasses move quicker, so there is your advantage. as for added weight, really that's not a concern for me.

Do hot gases move quicker? TBH the weight is marginal

Originally Posted by easy now andy

/ mine is mild steel, and i reckon you're talking bollocks. petrol exhaust gas temperatures are what? about 700c? an austenitic stainless such as 308 or 316 copes fine.

Exhaust gas temp is completely dependant on combustion conditions but 700c is unlikely to be minimum temp under any conditions (except idle) once the engine has warmed up, a more typical range is 1100 to 2400c IIRC

[easy now andy]

Originally Posted by protoborg

Do hot gases move quicker?

yes

TBH the weight is marginal

it was you that suggested it was a negative point, not me.

Exhaust gas temp is completely dependant on combustion conditions but 700c is unlikely to be minimum temp under any conditions (except idle) once the engine has warmed up, a more typical range is 1100 to 2400c IIRC

what!? you reckon the temperature in my exhaust is 1100 to 2400 centigrade?

composition depending, mild steel melts at about 1500c...

and i still thing you're still talking bollocks about stainless exhausts being affected by engine temps.

[Big Pete]

Exhaust wrap is not going to do anything noticeable (performance wise) on a normally aspirated bike. Its usually used for three things:

1 - keep nearby components from overheating, such as fuel/oil lines, wiring, electronics etc. However, you need more than 1 layer and its usually finish wrapped in ally foil to help reduce radiation losses.

2 - keeping heat in the exhaust gasses on turbo installations, more heat in the gas means more energy available to spin the turbo. However, similar comments apply as per above.

3 - cosmetics, in particular covering up welds, nothing wrong with that, but be warned, it has a tendency to hold water, and on a mild steel system, it can make the steel rot pretty quick.

[easy now andy]

Originally Posted by Big Pete

Exhaust wrap is not going to do anything noticeable (performance wise) on a normally aspirated bike. Its usually used for three things:

1 - keep nearby components from overheating, such as fuel/oil lines, wiring, electronics etc. However, you need more than 1 layer and its usually finish wrapped in ally foil to help reduce radiation losses.

2 - keeping heat in the exhaust gasses on turbo installations, more heat in the gas means more energy available to spin the turbo. However, similar comments apply as per above.

3 - cosmetics, in particular covering up welds, nothing wrong with that, but be warned, it has a tendency to hold water, and on a mild steel system, it can make the steel rot pretty quick.

the main reason i've installed it is to try and keep the temp between my legs down in the summer.

[Big Pete]

Originally Posted by easy now andy

yes



it was you that suggested it was a negative point, not me.



what!? you reckon the temperature in my exhaust is 1100 to 2400 centigrade?

composition depending, mild steel melts at about 1500c...

and i still thing you're still talking bollocks about stainless exhausts being affected by engine temps.

Your exhasut gas temperatures at the head could be 1100C or so, but the pipe isn't going to get anywhere near that. The head, being ally, would start to fail at about 350- 400C anyway. The metal temperature are a function of the gas temp, ambient temp, gas velocity inside and out, and the emmisivity effects of the pipe surface, amongst other things.

I would be amazed if the exhaust wrap increased the metal temps any more than 20-30C.

[Big Pete]

Originally Posted by easy now andy

the main reason i've installed it is to try and keep the temp between my legs down in the summer.

On an aircooled bike? You would be better sticking a couple of PC fans on to blow some cool air over your nads