CBR600f down pipe change

rowanh

So I went into Jp motorcycles about trading in my bike, they offered me 2k for it which I would have taken but I left it a few weeks and now due to my down pipes being knackered they are offering me 1200 for it which I am not that happy with..

I think I can get replacement pipes for around 100 euro, I am wondering if anyone can recommend someone in Dublin to swap them. I normally get the bike serviced in JP but the guy was basically saying if they do it chances are they will shear off the bolts and the engine will have to come out. Perhaps this just is the case with anyone but I would like to find someone a bit more confident in being able to do it if possible.. If it is going to end up costing 500 euro in labour its a bit pointless...

Ideally somewhere in south Dublin, I used to get Robbie in Mototechnics to service my previous bike, I will call him and see if he will do it any other suggestions?

Sonics2k

Can't recommend any mechanics in Dublin myself, but I can say having recently gotten it done on a Deauville you'll be lucky to get the downpipes for €100. Honda OEM parts are crazy expensive, and not many companies are doing 3rd party pipes, but it does depend on the year.

In my case it cost €350 for the full exhaust from Black Widow and about €200 for the work. Honda pipes are pain in the ass when they rot (which they will) and there is a massive chance of them sheering during the job. I've had mechanics walk away from the job.

Hotblack Desiato

I've removed and replaced downpipes on two fairly high mileage bikes, one Honda one Kawasaki, had no problems getting the nuts off. Just use a decent penetrating fluid first, apply several times over a period of about 24 hours and then give it a go. They'll only shear the studs off if you use too much force, if it's not budging then you'll have to try more penetrating fluid or heat.

rowanh

Right I might try to loosen them myself with penetrating fluid so and see what happens.

Here is a photo of the bolts

https://photos.app.goo.gl/M3m3LtD6k963LYV69

I presume too much force would be quite a bit?


I am not sure what they are called but the bits that the studs are going through which hold the pipes onto the bike. Would reusing them and the bolts be a bad idea and is there gaskets inside that need replacing?

Hotblack Desiato

If you don't have a torque wrench, get one or borrow one, you're not supposed to use them to undo fasteners, but get one anyway and set it to the recommended torque and tighten some random fastener you don't care about to that torque, so you get the feel of it.

Then use a plain bar or ratchet to undo the exhaust nut/bolt, using about the same level of force you did before. N.B. if the plain bar or ratchet is longer than the torque wrench, then move your hand up the bar so it's the same effective length, so you don't have extra leverage.

If it won't budge without using excessive force then apply more penetrating fluid, or heat. You could try running the engine until hot, big risk of burning yourself badly on the pipes though so wear long sleeves and leather garden gloves / old bike gloves. Engine off, squirt more penetrating fluid in and give it a go.

Some people give the socket head a good tap with a hammer when applying the loosening force, the theory is that this will break apart any corrosion and shock the fastener free. But the penetrating fluid is supposed to have done that job already.

There might be crushable aluminium gaskets between the pipes and head, if so these can't be reused. If the clamps are not part of the pipe then you can reuse them, and the nuts/bolts too if the threads and heads aren't damaged. Go to David Silver Spares or something and have a look at the parts fiche. You might be able to get a workshop manual free online too. I did this job on a '98CBR600 but I presume your bike is later. Can't remember if it had gaskets between the pipes and head or not. It's quite possible it didn't.

I used WD40 but it's not really a penetrating fluid, get Plusgas or something as this works much better.

rowanh

Thanks! Appreciate the advice

antiskeptic

It might be too late now but....

1. Shock is your friend. A large number of (firm but light enough) raps to the nut/stud combined and a large number of same raps to the nut itself (using a socket which is too small for the nut).

2, Penetrating fluid to the front of the nut, to the face where the nut meets flange and behind the flange (where the stud goes into the heat).

From this: you might as easily remove the nut and stud combined, from the head, as the nut from the stud

3. Time. Not sure whether you'll hinder by riding with fluid on - it will carbonize and perhaps add to the problem

4. Add tightening as well as loosening force the whole way out (or until its obvious things are loose enough to drive out. A bit of force to loosen, Then a bit of force to tighten. You're looking to break the seal and loosening a bit then tightening a bit will leave you with a zero by way of stripping but a plus in terms of breaking the seal. Like wobblying a fence post loose from the ground - you don't just push one way.