The place to come to share your technical expertise, or just find out what the little springy thing is that's just pinged out of sight under the work-bench.
She passed her MOT with no advisories but has been running quite rough at lowish revs. I read on here that it could be sticky valve. I took the exhaust off as all the fasteners on the valve cover disintegrated under very slight pressure. The valve is seized solid and I can't even get the cover off without bringing out the cutting disc.
As I see it I have 2 options. Buy a working set of pipes/valve or, cut the valve cover off, pull out the valve and then weld a plate over the hole.
The former is preferred. If I cut and weld will it work? Would I have to re-jet, etc?
Help please.
Do all you can to keep the Exup valve, the low revs are just pants without it and not heard of many success stories in getting them to run right without.
Maybe see if you can save the cover and drill the heads off the cover and plate screws. The screws can always be removed after although they seize good and take some work!
Alternately, Stig has reconditioned downpipes for sale occasionally, i'm sure he will be along sometime soon, so may be worth a talk with him
Keep the valve.......if exhaust is off the bike then its easier to work on...
Drill out the snapped bolts, start small and work you way up in bit size..you only need to go a couple of mm past the plate depth at this point..once past the plate, use a blow torch to heat EXHAUST chamber around valve cover, and tap the cover out GENTLY using SMALL hammer and small chisel (old flat screwdriver will suffice). Remember to tap it out away from exhaust as there is an internal lip on the cover.
Once your cover is off,if your valve is still seated internally. Get a can of maintenance spray (asda etc) and using the straw, and a flash light. Spray the collet/valve seat inside the exhaust.. Go have a brew and allow to soak.
Next, look at the opposite side of the exhaust. You will see an small round bump on the outside of the exhaust opposite the valve cover. GENTLY tap this bump with small hammer a couple of times. Now use blowtorch and heat said bump for about 30 seconds. Try and turn wiggle stuck valve out of place...repeat this step untill valve is out.
Use mole grips for a good solid grip and just try to get it turning first. Then a bit more heat and turn and pull.
Once valve is out, clean all moving areas (i use ultra fine wet/dry paper) but depends on your valve/damage etc. Grease liberally with high temp grease and set aside for now.
Go back to your valve opening and now drill out the 3 bolt holes. One hole goes straight into the exhaust. So thats easy.the other 2 holes are separate depths but use common sense here, and you'll be fine.
Again easier to start with a small bit and work your way up in thickness to near exact hole size..
TIP..drill one hole at a time. And put tape around your drill bits to same depth..
Re tap the holes and refit your fully greased exup valve..
Copper grease your new bolts on valve cover and fit them.
TIP.. Undo valve cover bolts @ 6 month intervals and re grease...service valve/grease internally every 12 months/winter..
If your pipes are solid. This should get you on the road again in around 3-4 hours depending on how many brews you have..
Hope this helps......
Please note....this is a method i have used, and worked for me..the key to success is patience when removing the stuck valve itself ..if any other members can add there tips or help in any way, feel free to add your comments.
You can heat the back of exhaust (valve) to cherry red
It will come out with a bit of persuasion but will be worth the effort.
Will put a smile on your face when back on road for sure
Try not to bend valve sideways when removing just turn as it should, I bent mine and I'm an engineer, it was a bit of work using centres in a lathe to get it back true again.
Good luck
Des
Only those who have been insane can prove there not insane! Can you ??? :-)
Alt being as you already have them off the bike, you could bring them over to mine and I'll have a look at what I can do with them
I'm just outside Mansfield Notts
As others have said try to retain the valve. Don't use the OEM headers without the valve in. If you're gunna lose the valve it's better to swap the headers for a set that's not designed to have a valve in in the first place such as Sandy headers
Depending on which year Exup you have you you'll need to leave a functioning servo connected as some models drop their cdi into limp mode if it's unplugged
Thanks to you all, especially Andy88.
I followed your tutorial as best I could but the valve cover was so bad it started cracking when I gently prised it off. Took ages to do. I managed to get everything moving and working properly and I put it all back together (minus chrome cover), put it back on the bike and after about 8 hours on the job, I took her out for a quick spin.
The difference is stunning.
So, thanks for the fabulous advice. Tea on me in Lincoln (if I go )
Really happy to hear that your up and running again.. And happy to help...
As for the tea.....
As long as you remembered to grease your bolts, Maintenance will take around an hour from now on...and thats a full strip,grease and rebuild..keep on top of the valve,,,its the most important neglected part of the machine ....
I'm gonna have to replace (at least) the valve cover as it is in such a bad and cracked state; probably this winter. Got to save some cash, then give it to Stig
but has been running quite rough at lowish revs. I read on here that it could be sticky valve. I took the exhaust off as all the fasteners on the valve cover disintegrated under very slight pressure. The valve is seized solid and I can't even get the cover off without bringing out the cutting disc.
)
