FZ6 (S2) exhaust header heavy rust - what to do?

[weylan]

Hello all, new member here.

Heavy, flaking rust on the flanges and nuts; lighter rust on the studs but still not great. The pipes just have autosol-curable surface rust. Picture here: https://drive.google.com/file/d/1D4gwSo_m6BejKZToSQXJsJQmavAz3_mh/view?usp=sharing

What do you suggest for the flanges and nuts?

1) Clean them up, apply Kurust or similar, then VHT anti-corrosion paint. Not aesthetically the best, but the paint will only be on the connecting joints so it won't be terrible. Have done this on an old car and it sort of works.
2) Replace the pipes with some in decent condition from ebay/bike breaker, plus stainless steel nuts and studs. I understand the risks of snapping studs - I'd get this job done professionally.
3) Leave them alone.
4) Any other ideas?!

All advice and warnings much appreciated!

Cheers

 

[TownsendsFJR1300]

Don't want to be the bad guy, but those flanges (all parts actually) are toast..

Your going to have a hard time removing those nuts without stripping/breaking them.

IMO, get another header, buy new head to header studs and nuts and replace all.

I suspect you'll be looking for a machine shop to remove several broken off studs..


That, ^^^, or run it till it leaks at the head and HAS TO BE ADDRESSED.


.

 

[Gary in NJ]

This is not surface corrosion. If you apply enough torque (the OEM spec is 20 Nm or 15 ft-lbs) to the replacement nuts to properly seal the gasket, you will likely crush what is remaining of the flange. As Scott has already pointed out, you are more than likely going to snap a few studs when attempting to remove the nuts. If you use penetrating oil and heat you may get lucky and remove the nuts without snapping the studs - but the studs should still be replaced.

 

[weylan]

Thank you Gary and Scott, I appreciate it. Thought that's what I'd hear but was hoping it wouldn't be! Will reduce my 2020 beer budget accordingly.

 

[Motogiro]

Welcome to the forum!

Agree with previous assessments. The nuts are likely not the original size anymore. From the picture I would cut that header off right at the flange so that you have clearance for nut/stud removal. Penetrating oil and physical shock are a good starting points Wet them and shock them with a drift and ball peen. Let them sit for some time and then shock and oil again. If you're patient they will move. I also always pray before I use my most colorful curse words and phrases. The praying and cursing may not move the lil bastards but it helps relieve stress.

 

[FinalImpact]

Them be some Fugly nuts you have there.... I'd start a week out by spraying anything you intend to touch and ride it if possible. It will smoke and stink but that is in your favor. Automatic transmission fluid does wonders too. Don't discount it...

There should be some fleabay options out there. But ya, them gonna break shearing studs at flange level making a long day.

When you get one stud out, insert a long bolt in there as a guide for drilling the others. Grinding what is left flat will make it easier to center punch...


What does the rest of the bike look like?

 

[Cloggy]

TBH I had the same problem with my FZ6, my mechanic said it could be fixed by a good mechanic but would be a long process, so you have to either have a lot of time or know a good mechanic to fix this. As my bike had over 150,000 km's on the clock and had another problem with the ECU it wasn't financially viable and would bring more in by selling it for parts.
This is my own fault as I rode in all weathers and the bike stood outside permanently. Luckily I have a garage now for my new bike.
I can understand if you have a low milage bike or if you are willing to put the time/money in that you will be looking to repair this, I would be interested to hear how you get on .

BTW welcome to the forum Weylan.

 

[ktp1598]

Weylan, where are you located? I have a near perfect S2 header (needed an S1) if you're in the States. I've even got the nuts that go with it though they're not as nice but are much nicer than yours. Make sure you buy the studs at a Yamaha dealer as the ones on eBay and Amazon are severely overpriced. I paid less than $3 each for the couple that I needed.

 

[weylan]

Hi everyone, thanks for your replies and sorry I'm so late getting back to you! Hope you're all well.

KTP: I would have jumped on your offer but I'm in the UK. Thanks for the tip on the studs. And yes, most things (including the contents of my septic tank) are in better nick than those studs.

I bought some headers from a breaker which I'm polishing up before I find the courage to start on this job. Lockdown seems a good time to start, but I'm pretty nervous about messing up so I may end up waiting until things get leaky. I'll keep you updated...

The rest of the bike is fine, other than the odd scratch (and some more rust!). It was standing for about 2 years and had no MOT when I bought it so I spent a few weekends freshening it up (new air filter made the world of difference). My gosh these things can fly! I've ridden it pretty much every day since I first posted here; it's been rock solid and a lot of fun.

By the way, I just bought an old CBR400RR for a bit of a lockdown tinker. I've always wanted to own one. I'll let you know how it compares (don't worry, it will always be a second bike!).