Author Topic: Chrome going brown (Read 15739 times)

SimonT · **on:** April 10, 2011, 10:39:11 pm

Hey Guys

The chrome on my exhaust is going a goldy brown colour. Just wondering what is causing it, and how do i remove it?

Ducati Scotty · **Reply #1 on:** April 10, 2011, 11:58:27 pm

When chrome gets hot it tends to discolor. I've heard that it's the impurities in the metal pushing out. I think it's really just oxidation.

I see this in two main spots on the new bikes: right near the head and about 3/4 back on the lower part of the muffler. The stock pipe probably has pretty good back pressure because of the catalytic converter, it's both an inherent restriction and needs to be hot to work. This causes the hot gases to be held in and really raise the temp in spots. Near the head is as hot as it gets. I suspect that the part of the muffler that turns color is either a constriction (the catalytic converter) or an internal bend that reverses the gas's direction.

You can use metal polish and a lot of elbow grease, this will often take care of it or at least minimize it. In the long run it will come back. Your best bet is to get an aftermarket muffler without a catalytic converter. This allows the gases to flow out more easily and lowers the overall temperature.

Hope this helps,

Scott

SimonT · **Reply #2 on:** April 11, 2011, 12:07:46 am

you were spot on with your locations....

a bit near the engine... and the other bit formed a bit of a band around the muffler.

That sux if its going to keep coming back

it appeared after my first highway stint. So im guessing it was the higher RMP for a longer period of time.

So... what pipe should i look at getting?

singhg5 · **Reply #3 on:** April 11, 2011, 12:31:26 am

Quote from: SimonT on April 11, 2011, 12:07:46 am

That sux if its going to keep coming back .....So... what pipe should i look at getting?

Simon:

The golden / brown color on the pipe is a sign that you have been riding the bike well ! The pipes last many miles, even with the color. In my opinion there is no need to spend money on getting a new pipe unless the performance is affected. Just look at the scenery when riding the bike

. and spend the money on Fosters lager and some good food.

GreenMachine · **Reply #4 on:** April 11, 2011, 01:00:15 am

exactly..i'll be dam if i'm gonna try to get that brown n blue spot on my header pipe cleaned off....life 2 short to give a shit about that...a foster be good right around now...haven't had 1 of them in a long time mate..

SimonT · **Reply #5 on:** April 11, 2011, 01:15:28 am

im not too worried about the one on the header... but the one on the muffler looks gross hehe...

Btw... Fosters = gross

They dont even really sell it here in Australia.

There are plenty of other local beers which are actually drinkable

bob bezin · **Reply #6 on:** April 11, 2011, 01:22:44 am

the discoloration is normal. usually the pipes on most bilkes turn blue eventyually. don't worry enjoy the ride.the pipes on my 04 triumph are almost black due to the restrictons in the mufflers. my enfield pipes are getting blue . no big deal.

GreenMachine · **Reply #7 on:** April 11, 2011, 01:45:57 am

actually i haven't had a fosters for a few years...guess i won't get it then...plenty of local microbeers to get my hands on....keep polishing that pipe joint..

Ducati Scotty · **Reply #8 on:** April 11, 2011, 02:23:51 am

I'd say what's been said: ride and don't worry. If you really can't stand the discoloration there are two period appropriate style pipes available:
http://nfieldgear.com/enfield-store/aftermarket-parts-accessories/exhaust/efi-silencer.html
There's also an upswept model but you can only get that through the dealer. They're both a little louder than stock and give a modest performance improvement over stock according to reports here on this forum. The upswept is the louder of the two.

Also, we have a 1 3/4" head pipe. This is the same size as most modern Harleys. So there are plenty of aftermarket options out there that you can use so long as you can get or make a bracket to support it.

Scott

Chris-G5 · **Reply #9 on:** April 11, 2011, 04:41:20 am

The best stuff for removing discoloration on chrome pipes is Blue Job. It takes some work by hand or you can use an orbital sander like in this video.

http://www.youtube.com/watch?v=BWaChZa5htg

Here is an inexpensive silencer that I have on my G5. You can't beat the price even if the shipping is the same as the $37.99 price. It's like the "EFI silencer" from nfield gear.
The inner diameter is 1 3/4" and the head pipe has an outer diameter of 1 5/8" So you'll need a short pipe to insert into the silencer to reduce the inner diameter to 1 5/8". I got a 4" pipe form the auto parts store that worked perfect.

http://cgi.ebay.com/ebaymotors/CHROME-ROYAL-ENFIELD-500cc-ELECTRA-SILENCER-ASSLY-NEW-_W0QQcmdZViewItemQQhashZitem1e62c467c9QQitemZ130506057673QQptZMotorcyclesQ5fPartsQ5fAccessories#ht_6544wt_1167

REpozer · **Reply #10 on:** April 11, 2011, 05:32:01 am

Hmm, guess mine never gets hot enough to discolor.

GreenMachine · **Reply #11 on:** April 11, 2011, 04:06:14 pm

I remember when the bike was new and breaking it in (winter) that OEM header pipe would get blue and purple and hot as the dickens. Got a new exhaust system, re jetted and she just has that golden brown look 4 " above the neck ,no browning at the muffler joint....
In retrospect I probably should have coated the header pipe when I brought it new as
the coating hardens overnight and supposedly acts like a insulator and cuts down on the heat transfer to the pipe. U can't coat the inside of a used pipe ...rambling thoughts for the morning chat.

REpozer · **Reply #12 on:** April 11, 2011, 04:42:54 pm

Coated with what?

GreenMachine · **Reply #13 on:** April 11, 2011, 05:10:25 pm

google exhaust coating and take your pick..external or internal...if i ever order a new complete exhaust system for the enfield, I would consider doing this to see if their is any improvement on look and performance...It could be voodoo science too...and cost would be a factor..Guess u could Kreeme a new exhaust and c what that does for u..U know that blue crap in a bottle for 30 bucks....has to be for a new virgin pipe and let it cure for a day or two...

“Internal Exhaust Coating”
For protecting chrome pipes or for those wishing to impart the maximum thermal barrier properties, and obtain a smother interior surface for enhanced exhaust flow.

A ceramic based coating used as an internal lining to achieve maximum insulating properties between exhaust gases and the metal surface. The greatest benefit is realized at the area where the exhaust hits the first bend in the pipe, however a complete lining will result in maximum benefit. Great for exhaust ports. Pipes must be new to be guaranteed.

Minimize or in most cases eliminate chrome pipe bluing
Obtain maximum thermal barrier properties
Improve exhaust gas velocity, increase hp.
Our coating service includes all necessary preparation for coating adhesion.

Pricing upon request

Ducati Scotty · **Reply #14 on:** April 11, 2011, 06:04:12 pm

Three cans of flat black Krylon and you won't care what the shiny bits look like. Sometimes I miss the complete lack of needing to ever wash your bike when you own a Dark Ducati.

Scott

GreenMachine · **Reply #15 on:** April 12, 2011, 12:25:48 am

i should wash my bikes more and polish them...they look okay and are garaged most of the time...i got to be in the mood for cleaning..

Ducati Scotty · **Reply #16 on:** April 12, 2011, 12:57:31 am

A wash and polish becomes its own incnetive. I always marvel at how my car seems to completely change color and look so much better when I wash it. The C5 is looking pretty dull after a winter riding season here in Portland, OR without a wash.

Scott

1Blackwolf1 · **Reply #17 on:** April 12, 2011, 03:17:21 am

Heck my India exhaust is turning black were the chrome burned off. The rest is a deep copper color. Looks very period correct..patina man, patina.

Tecomakeith · **Reply #18 on:** April 12, 2011, 07:06:23 am

I will agree with you about Fosters, heep of horrible goo in a bottle from The Fosters Group.

Try a Kilkenny or a Beck's that's all I drink now. VB was given me to many headaches but that might have been my other half also

I wouldn't worry too much about the dis-colourization, my C5 has done the same.

Quote from: SimonT on April 11, 2011, 01:15:28 am

im not too worried about the one on the header... but the one on the muffler looks gross hehe...

Btw... Fosters = gross They dont even really sell it here in Australia.

There are plenty of other local beers which are actually drinkable

GreenMachine · **Reply #19 on:** April 12, 2011, 01:55:32 pm

i think the wee bit of discolor gives it character...funny u guys say foster gives u a headache down under...budweiser does the same thing to me...just one and i have to take a asprin a hour later....i like becks (clean beer) and yes the local microbeers have taken off here too and that a good thing...I could see the Indian made exhaust turning a bit darker than the Brit made or affrmarket exhaust systems..But they are half the cost (usually)..

SimonT · **Reply #20 on:** April 12, 2011, 10:51:25 pm

Quote from: Tecomakeith on April 12, 2011, 07:06:23 am

I will agree with you about Fosters, heep of horrible goo in a bottle from The Fosters Group.

Try a Kilkenny or a Beck's that's all I drink now. VB was given me to many headaches but that might have been my other half also

I wouldn't worry too much about the dis-colourization, my C5 has done the same.

Hey Keith,
are you from Aus?
Im a fan of stuff from coopers and little creatures breweries..... *licks lips*

Thanks for the input guys.. ill see if it polishes off easily, otherwise ill leave it alone.

Tecomakeith · **Reply #21 on:** April 13, 2011, 01:26:20 am

Down in old Melbourne.

Had a run in Tassie early March on my C5 with 22 other bikes mostly HD's, did about 2000klm's over the week. Great ride, hopefully we will be doing it again next year.

All of us are over 50, old farts

Quote from: SimonT on April 12, 2011, 10:51:25 pm

Hey Keith,
are you from Aus?
Im a fan of stuff from coopers and little creatures breweries..... *licks lips*

Thanks for the input guys.. ill see if it polishes off easily, otherwise ill leave it alone.

SimonT · **Reply #22 on:** April 13, 2011, 01:48:51 am

that sounds like a blast... i want to do something like that

the weather is perfect for that up in qld at the moment

Andy · **Reply #23 on:** April 13, 2011, 01:59:35 am

Quote from: SimonT on April 11, 2011, 01:15:28 am

im not too worried about the one on the header... but the one on the muffler looks gross hehe...

It's normal - look at mine. Makes me want to hurl. The catalytic converter in the bike (am I the only one who thinks catalytic converter and bike should never be used in the same sentence?) is the cause.

olhogrider · **Reply #24 on:** April 13, 2011, 02:22:29 am

The upswept (no cat-con) did the same thing. The real culprit is an extremely lean mixture. We need that for smog and mileage. For years Harley has run a cover over the mufflers to cover it up. The Enfield headpipe is double walled but not the muffler.

Chris-G5 · **Reply #25 on:** April 13, 2011, 02:28:43 am

Quote from: Andy on April 13, 2011, 01:59:35 am

It's normal - look at mine. Makes me want to hurl. The catalytic converter in the bike (am I the only one who thinks catalytic converter and bike should never be used in the same sentence?) is the cause.

Did you modify your brake pedal? No rubber and it's up higher than stock.

SimonT · **Reply #26 on:** April 13, 2011, 02:31:32 am

oh man... yeh thats exactly like mine, same spot and all....

Andy · **Reply #27 on:** April 13, 2011, 03:19:42 am

Quote from: Chris-G5 on April 13, 2011, 02:28:43 am

Did you modify your brake pedal? No rubber and it's up higher than stock.

Yes - crash modified - I don't recommend it.

GreenMachine · **Reply #28 on:** April 13, 2011, 04:26:54 pm

its called government restrictions

. U should be use to them by now and probably more to come...Think of it being totally black (I don't mean painted) and the bike won't start period...Just think of the great gas milegae u can brag about.....u can then put it in the front yard as a ornament and put a basket on the front and let the wife put some pansies in there....well u get the point.....get the thing off and let her breathe It s a very nice machine u have there and she deserves better