Header Wrap

[Toast]

Here's a pic of my header wrapped:

The wrap is a beige color but I painted it after it was wrapped.

It definitely makes a difference. The bike seems to have lost just a little bottom end but is pulling better on top. I have a 45 slow jet, needle clip in the 4th slot & a 120 main jet. The 125 jet was a little too fat I think a 122 may be the ticket. The bike is not popping or backfiring in any of the circuits. However, I think it may be on the lean side in the middle circuit, affecting it's ability to wheelie in second. So, I'll move the needle down to the 5th slot & see if that helps it pull better. It's on the edge of being too fat with the pilot screw. So, I can't get any more there.

I think this mod will be great for running enduros where it's flat out fast all the time. For some of the nastier goaty trails this mod so far is a bit of a negative (not much) but that may change with some jetting changes.

?

[Guest RIDE_for_RED]

im at 300 above s.l. and i have the same setup as you expect i have the 122 main. (accually a 122.5 **1/2**)

yet it still pops, pondering about a 125main.

if you wanna sell ur 125m give me a "ringgy" ?

[250Thumpher]

Is it popping on decel? If so, than it is not your main jet. Reread the stickey for what circuit controlls which opening.

[Guest RIDE_for_RED]

250Thumpher i am truely impressed by how much thought you have sunken into the stickey. I never looked at it again after i first read it. (about 2months ago.)

********TO EVERYONE ELSE, IF YOU HAVENT ALREADY LOOKED AT THE STICKEY AND YET YOU STILL HAVE QUESTIONS, LOOK AGAIN.*******

250Thumpher ???

[Toast]

Actually, too big of a main jet can cause some popping with a sudden turn off of the throttle. A little different than just having the throttle closed but still popping caused by the main being too fat. I've had it & fixed it by going smaller on the main jet.

[Toast]

Just a jetting update on the header wrap mod.

45 pilot, clip in 5th slot(lowest) on power up needle,120 MJ

Moving the clip down one was the ticket! ? Pulls the front wheel up better in 2nd gear then it did with it in the 4th.

?

[Guest RIDE_for_RED]

Hey toast, mind telling us ur elevation, average temp, weight, you know........ stuff like that?????

[Toast]

elevation: 200-2500ft

temperature: 50-60 deg

This bike is super light! ?? Weighs less than I do with gear on. ?

Does that help you?

[Christian Wildman]

You are going the wrong way,Brother. !st drop the clip to raise the needle to clean it up &/or start dropping down on the main jet size.

[Guest RIDE_for_RED]

You are going the wrong way,Brother. !st drop the clip to raise the needle to clean it up &/or start dropping down on the main jet size.

brother? also, who might you be speaking to? Me, Toast? 250Thumper???

[RedMesa]

I have a heat shield over my PowerBomb which helps with quick light contacts from the side.

Yesterday I fell which is not unusual. But for the first time my right back of knee really hit the header. I got off fast but it melted through my Klim pants and tights underneath and then stopped. But I was left with a blister.

As you can see in the pic, there is melted nylon within two inches of the exhaust port. Something about this fall really got my leg in there.

Given that I have been trapped under the bike for several minutes at a time in rocks, this experience got me thinking about reducing the header risk. Having a 500 degree surface inches from your body is not the safest design.

Seems like an exhaust wrap would help reduce the surface temperature. Yes, it will increase head temperatures somewhat but I do run synthetic oil.

https://www.amazon.com/SunplusTrade-Exhaust-Motorcycle-Fiberglass-Stainless/dp/B01KVYH66U/

And I am willing to give up some engine life or whatever for increased safety. This was a very small burn but it gave a strong hint.

Anything I am overlooking?

[Chuck.]

After all of these years I finally put a factory heat shield on an after market header. But your post now make me worry about the 1st bend. ?

 

[Daniel627]

I think when I finally get the XRs Only header, I'm gonna have my friend tig weld on a couple stainless bungs so I can mount the factory heat shield. 

RedMesa has a good idea by using one with the hose clamps. However, it really doesn't have an air gap between the shield and header to allow it to flow air and make a big temperature difference.

I still gotta drill out one of the broken screws from my head pipe so I can mount the heat shield back on. 

[RedMesa]

16 minutes ago, Daniel627 said:

However, it really doesn't have an air gap between the shield and header to allow it to flow air and make a big temperature difference.

You can't see it in the picture, but there are standoffs of 1/2-inch aluminum U-channel between the shield and the pipe. This does provide an air gap and reduces temperatures somewhat.

The standoffs are mentioned in the PowerBomb writeup here http://bit.ly/2FicPDF

Edited November 12, 2018 by RedMesa

[Daniel627]

Ah gotcha. Guess the angle doesn't show it very well

[Chuck.]

On 11/11/2018 at 6:56 PM, Daniel627 said:

I think when I finally get the XRs Only header, I'm gonna have my friend tig weld on a couple stainless bungs so I can mount the factory heat shield. 

RedMesa has a good idea by using one with the hose clamps. However, it really doesn't have an air gap between the shield and header to allow it to flow air and make a big temperature difference.

I still gotta drill out one of the broken screws from my head pipe so I can mount the heat shield back on. 

I installed a stock XR200R heat shield on a XRsOnly header and it was easy. Since I didn't know exactly where the best location would be I used hose clamps to hold nuts against the header, just punch a hole in the band for the heat shield bolts. The air gap will be the height of the nuts. I found regular Honda nuts provided enough air gap.  Loosen the clamps a bit and you can move the heat shield around to find a good position. After a few rides the nuts will leave marks on the header to use for welding. 

Edited November 17, 2018 by Chuck.