Yes I'd expect the servo to be there ... it's only place the cables attach to other than the exhaust.

I'd still take off the carbs and have a look - judge what you see in the float chambers - if it's all yellow tarnish and brown residue then your looking to clean them thourghly, if it looks reasonably clean you you be able to spray the float chambers and down the jets.
You need to look at the jet sizes standard are, outside carbs (1 and 4) 100, the middle carbs (2 and 3) are 97.5

Clean the othside of the carbs with parrafin and a small paint brush then get a big sheet of white paper to work on so you can see any small bits. Work on one carb at a time so you don't get any parts muddled up.
When you take off the float chambers use something with a scewdriver bit and make sure it fits properly - (I use a 1/4" drive ratchet) push down hard on the screw and then turn it otherwise they round off (bloody things !!!) usually people replace them with allen head screws. Use the same technique with the carb tops, they have a soft spring below them. Check the rubber diaphram - spray some carb cleaner on it and if there's a pinhole you'll see it. Lift the diaphram and the slide out then lift the neeedle out write down where the circlip is on the needle. Clean it up and put it all back.
You just have to be methodical with this job.

Thank you for a great post! Spoke to some dyno centres and they agreed with your diagnosis!
One centre wanted to jet around the exup so I still didn't have it and the other said exup should be there and they will jet the exhaust if you see what I mean! Trouble is the bike can't be ridden like it iis so have to fit exup and get it running well enough to take on the road.

When you have a mo can you tell me how to adjust the exup? I am driving to Neil"s on ties to collect pipes and exup. I know how to fit the valve but which cable goes in what hole both on the exup and servo ?
Then how to you adjust it when the right cables are in the right holes!

Thanks owe you a few drinks!
Mark

Page 41 of the service manual http://www.400greybike.com/docs.htm gives you a diagram of the parts .... and page 44 has the carbs diagram on it. It's a large file to download but it has all the pages bookmarked and it's a lot clearer han most of the pther ones you'll find on line.

Anyway - when you turn the ignition on the first cable that moves is the one to open it and that goes on the top the other closes and goes on the bottom.
Undo the bolts holding the servo on, follow the cables from the top and you'll see some adjusters, slacken them off.
Take the pulley off, attach the cables at to the pulley and put some tape on to hold them, put the pulley on the exup with the little tongues facing forward. Stick a bolt or pin through the tonques and into the hole behind it so it's locked in the forward position. Now bolt the servo back on. Adjust the the cables - finger tight only - and do up the locknuts. Take the bolt / pin out from the pulley turn the ignition on. The valve should rotate clockwise / anticlockwise and return to the same forward position. See if it runs.

Your great! So the adjusters are at the servo end? It's killing me having to wait till to
Ties to get it
Mark

exup maintenance just as Mr evil said but with pics
http://www.cartestsoftware.com/fz1/exupmaintenance.html

when i said check the carb boot manifolds it was as part of the routine carb maintenance and not a diagnosis, (these are often forgotten or not considered part of the carb system but they are and quite important, they take the fuel/air mix into the cylinder head and if their damaged any extra air in the mix will make it run incorrectly)

as has been said before if you don't work through the system methodically and make sure each piece of the puzzle is working correctly you will never know which piece is letting you down

Thank you, I think I might fit exup first and see if there is anydiffernce then do the carbs as I will be going on holiday Friday week for two weeks and doing the carbs is what I am most nervous about.

Reminds me of my moped days when I had a garelli tiger cross, shows my age , drill the baffles for more noise and it went slower. Remove the baffles even noisier and went very slow! No backpressure but I loved that bike apart from. The number of crankshafts it went through!
Regards

Just one thing, if when i take the cover off my exup, there is supposed to be a bush in the other side of the pipe for the valve to fir in. This maybe there maybe not? presumably when i take apart the new exhaust im geting as the exup is still there the bush should be in place. If need be how to I get that bush out if I need it? is it a loose fiting and will come out? What is the best way of getting it out? (Try filling it with grease and use a drift, hit the drift with hammer and grease will push it out?)

Is there an easier way?

Thanks
Mark

If I have 2 loose exup cables can I tell which is number 1 (opening cable) and number 2 (closing cable).
Thanks you people are great!
Mark

MarkT wrote:If I have 2 loose exup cables can I tell which is number 1 (opening cable) and number 2 (closing cable).
Mark

Hogdigerdy Dog wrote:exup maintenance just as Mr evil said but with pics
http://www.cartestsoftware.com/fz1/exupmaintenance.html

If the exup is in the exhaust and moves ... leave it alone.
Get your bike sorted and running first before doing this because the bolts holding the exup in will have rusted and will break.