Refurbing my EXUP

Post by **nugget** » Mon Oct 17, 2016 6:50 pm

It's good to keep yourself busy. Also very rewarding.

Post by **Stig** » Mon Oct 17, 2016 7:11 pm

I've just resigned myself to selling off more bits, some of which involve splitting and selling a set of carbs. If you need a carb top and diaphram give me a shout

Post by **Stig** » Mon Oct 17, 2016 7:26 pm

The set I'm about to part out have Dynojet needles fitted

pilninggas · Post by **pilninggas** » Fri Nov 11, 2016 8:09 pm

Just got it fired up, sounds sweet as fook. Filled the garage with some pretty noxious fumes,

. Revs out nicely. Makes me realise how sanitised my FZ1 sounds (even with a decat and airbox mod).

A few bits to tweak before carbs are secured.

Does anyone remember what car rad cap fits (is it a mazda or a mitsu?), the rad cap rubber is in an awful way and I don't want to chance it causing major heart ache.

pilninggas · Post by **pilninggas** » Sun Jan 15, 2017 4:21 pm

Things are getting done at a steady pace on the old girl.

Pulled the downpipes off, so as to make sure the EXUP valve was fully functional. As it was it was not free, so the usual strip down was commenced--

After getting it all apart I retapped the cover holes and regreased the bushing with ceramic grease.

The trouble is on reassembly when I tighten the cover down the valve (which turns freely when the cover is down all the way) it binds. I checked the bushing on the far side, it's smooth and free of swarf and debris. As far as I can tell the valve is straight (if I get chance at work I will set it in a vee block and check for sure).

Is there anything else to look for that might make it bind-up. I've rebuilt a few over the years and not had this happen before. I don't think i ever been this fastidious about an exup rebuild either, yet it's giving me the most agro, any advice would be much appreciated....

Post by **Stig** » Sun Jan 15, 2017 5:19 pm

If you have access to a lathe put the valve between centres and rotate by hand. You can then either use a dial guage or I use a pointed lathe tool to test against the shaft. It takes a few goes of taking the valve out the lathe and holding it in a vice to tap the shaft in the required direction

Btw, you only just need enough pressure against the ends of the valve to hold it in situ... if you give it too much pressure the valve end will flex to give a false reading

Post by **Stig** » Sun Jan 15, 2017 5:32 pm

Both shafts must run parallel to each other for the valve to rotate freely when assembled

itsnotagenesis · Post by **itsnotagenesis** » Sun Jan 15, 2017 8:24 pm

Is there a metal gasket between the exhaust and the plate?
I am sure I had this problem and the gasket on mine was either missing or never there. After buying and installing the gasket it was fine.
Im also sure that not all models had this gasket either.

Post by **Stig** » Sun Jan 15, 2017 8:45 pm

Not all have the gasket as standard. It's a bit hit and miss which ones did and I've not been able to establish a pattern from the many sets of headers I've had and refurbed

Post by **nugget** » Sun Jan 15, 2017 8:47 pm

Going by memory, my bike has a gasket fitted.

Post by **Stig** » Sun Jan 15, 2017 9:11 pm

So does mine

roadrunner · Post by **roadrunner** » Mon Jan 16, 2017 3:02 pm

And mine!

Post by **Stig** » Mon Jan 16, 2017 3:04 pm

All that said...... most will work perfectly well without the gasket as long as the shaft ends are aligned correctly

pilninggas · Post by **pilninggas** » Thu Jan 19, 2017 7:32 pm

Thanks for the advice.

Finally got chance to take it into work today. Put it in the lathe chuck and then set the tool so I could see the run-out. Was 4mm! not wonder it was binding up. Carefully retrued it.

Then put it in a vee block and check the vertical and lateral displacement. Got it down to about 0.25mm.

Just reassembled it and not binding whatsover.

Thanks chaps.

Jay762 · Post by **Jay762** » Fri Jan 20, 2017 10:52 am

Just to add my 2p - I am currently running gasket less