Grinding down header weld 98+ How-To (56K?)

[BlackburnD]

I have seen a couple times on here from a few differnt people about grinding down the header welds on the 98+ Kats. For some reason Suzuki welded that flages of the header on the inside, and not very well mind you. These welds tend stick up a couple of milimeters and restrict exhaust a bit.
Some on here have grinded them down to make for better exhaust flow.

Here is a how to for this free mod.

Tools needed. Luckily not much is needed for this job. Allen wrenches for removing the fairings, and header. Socket and ratchet set to remove the mid pipe from the header. A grinder of some sort. I used a dremel. Anti- Sieze. Something I suggest but is not absolutely necessary is some form of rust penetrant. There are several on the market. I love the Mopar stuff.



First thing to do if you so choose to use a rust penetrant is spray the header bolts as seen here, and let them sit.


You may also want to spray some on the bolt for the clamp for where the mid-pipe and header go together. The head for this bolt is on the right side of the bike as seen here.


After that it's time to remove the lower cowling/ air scoop. There are a total of 5 allen head bolts on each side.. There is one each side that are farther back than the others. Basically under the center stand.
Shown Here.



Though I am not sure if it is necessary to remove the upper fairings I did it anyhow, as I was doing some other work to the bike while I had it apart. Removing the upper fairings will give you more room to work, but I am not positive it is necessary.


Now you are ready to get into the real work. Not a bad time to respray those header bolts if you are using a rust penetrant. Now remove the bolt for the clamp mentioned earlier.

Now it's time to remove the header bolts. It would be wise to use 2 of the bolts in the 2 and 3 cylinder to support the header until you are ready to fully remove it. Once all of the head bolts are out gently remove the header from the mid-pipe. Be careful if you plan to use the old exhaust gasket for the mid-pipe connection. Removing the header from the pipe may take a little twisting and effort, but it will come out.

By now you should have the header out and on the ground or work bench.


If you take your finger and put in the pipes and rub the edge you will feel the welds you are about to grind down. Now it's time to do some grinding. I started using the sanding wheels on my dremel, but needless to say that did not do such a great job. After 4 sanding drums, and only one port ground down I gave up and went and got the grinding stone attachment for the dremel. Unfortunately the pictures of the finished product did not turn out so good, but when you are finished the inside of the pipe where that flange and pipe meet should be smooth.

Now clean off the thread of the bolts for the header, and the clamp. A wire wheel on a grinder if available will work great, or just get an attachment for whichever tool you are using to do the grinding. Once the bolts are clean put some anti-sieze on them and reinstall the header. I put a little of the spray on anti-sieze on the end of my mid-pipe to make it easier to remove if it needs to be taken off at a later date. This is of course optional.


Now just put the bike back together. You will not notice a big difference in the power of the bike, but it will have an affect. If you just keep in mind that an engine is nothing more than a big air pump you will understand why this little bit of restriction in the pipe will help.



If anyone has any questions about this little mod feel free to ask. I assure it's not difficult to accomplish.

If this thread needs to be moved feel free to move it. If this seems helpful please feel free to sticky. Good Luck and happy Modding.

Doug Blackburn

[LiquidRider]

I want to do this, but will I have to change my jet at all? I am already making it .5 turns richer....do I really have to jet?

[LiquidRider]

Anybody?

[GregS]

This mod shouldn't change the idle mixture which is what you adjust with the screw you mentioned. If the weld were particularly large it could affect main jet sizing but more likely not.

[steves]

Originally Posted by KatCanDo

I want to do this, but will I have to change my jet at all? I am already making it .5 turns richer....do I really have to jet?

You shouldn't have to jet unless you move up to a 750 header or full system.

[LiquidRider]

Thanks for the help! Purchasing Dremel bits today

[jwonton]

nice write up. (just got done grinding my welds)helped me out a lot! i found the brown dremel grinding stones to work the best. plan on going through a few though. i used wd-40 on the header bolts as that's all i had. sprayed the header bolts removed the plastics had a beer spayed again had a beer. the header bolts came out pretty easily. i think the anti-sieze will help a lot if i need to remove anything in the future.

[The CyberPoet]

The write up already exists in my website here, including details of which Dremel attachments you need, etc.:
http://www.motorcycleanchor.com/katana/header.html

Cheers,
=-= The CyberPoet

[md86]

Yeah , but NOW it's HERE , too !

[KatanaSoldier]

for newbs