How to check choke plungers?

[yorkie_chris]

http://www.youtube.com/watch?v=uc7uyMs-YtQ


There is writeup by TSM on main site somewhere about how to remove carbs to de-restrict. Taking them off bike is best way. Avoids stressing throttle cables and rounding the heads out.

[Dave20046]

The SV carbs possibly have drain screws at the bottom of the bowls, to drain the tank I guess you could remove it and take the tap off (bit messy) or syphon it out. then ensure the hose is clear and refill (I'd probably refill with super unleaded).
Don't know whether I'd start with the tank or the choke plungers - diagnosing stuff's the hard bit.

[yorkie_chris]

You can draw a bit of fuel off to see if there is water in without removing carbs.

If bike is new to you then IMO take the carbs off. Gives you chance to grease everything, strip stuff down and copperslip it, replace any important fasteners. Depends what miles you're going to do though.

[5hort5]

Chris - not meaning to high jack this thread but what bits need greasing and what bits coppersliping in the carb please? Will have a go at that along with the valve clearances on the weekend.

[embee]

Very good guides given above.

In case it's any help,
1 - the screws are crosshead/Phillips, DO NOT try to use a Pozidrive bit, they are different and don't fit properly and WILL round the heads out.
2 - it's much better to use a driver bit with a small socket set, or a T-handle etc, it's much easier to apply good pressure to keep the bit engaged in the screw while turning, a normal screwdriver type inevitably ends up getting angled over and turning out the screwhead.
3 - proper penetrating oil is best by far. WD40 sort of works a bit, but it isn't designed as a penetrating oil so is second best.
4 - I always recommend fitting the driver into the screw and giving a LIGHT tap with a small hammer first to help break any sticking. Ideally a metal driver works better than a plastic handled one which absorbs the shock. Note the warnings about carbs being fairly delicate, so easy does it.
5 - if the screw shows any sign at all of rounding out, STOP, then gently tap the screwhead back down with a small hammer (and maybe a steel drift as necessary due to access) to reform the metal and tap the driver into it again.
6 - When reassembling, any sort of lube is better than none. Avoid getting grease down in the plunger bores before the plungers go in, but grease behind them on the springs is fine.
7 - water and crud accumulates in the float bowls, so it's worth draining them occasionally anyway. The drain screws are allen head items set into the sides of the float bowls which you only need to slacken off a couple of turns and the fuel drains out of a drilling in the bottom (imagine a right angle passage with the screw coming in from the side to plug one of the legs, if that makes sense?)

[yorkie_chris]

Originally Posted by 5hort5

Chris - not meaning to high jack this thread but what bits need greasing and what bits coppersliping in the carb please? Will have a go at that along with the valve clearances on the weekend.

Don't copperslip anything inside the carb itself, only things you copperslip are screws and fasteners like choke plunger screws.

I get plastic bag on the end of choke cable, let engine oil drip through overnight. Then get spray grease and squirt the splitter as full as possible. Spray some behind springs on plungers and work cable around. Also good dollop around the O-ring seal outside the plunger housing.

Originally Posted by embee

6 - When reassembling, any sort of lube is better than none. Avoid getting grease down in the plunger bores before the plungers go in, but grease behind them on the springs is fine.

Can't see a bit causing a problem, it would soon get sucked through that passage. Don't put grease gun down the hole though

Hey I was thinking last night, I had a service a few weeks ago, and he said he squirted some oil onto the choke plungers because he knows it's a problem on that bike. Is it possible for it to still be the case? Or should I be looking elsewhere?

It was a full service, would he have checked for stuff like water in the tank as well? And various other...carb...things?

[fizzwheel]

Allan - what exactly is the problem with your bike you are trying to fix ?

Its quite possible that the mechanic that did your service checked all those things, but then its also quite possible that he didnt... depends how much you trust the mechanic that did the work.

[yorkie_chris]

Originally Posted by allantheboss

Hey I was thinking last night, I had a service a few weeks ago, and he said he squirted some oil onto the choke plungers because he knows it's a problem on that bike. Is it possible for it to still be the case? Or should I be looking elsewhere?

It was a full service, would he have checked for stuff like water in the tank as well? And various other...carb...things?

It is not lack of oil that makes them stick, water gets in and corrosion powder jams them. You need to clean them and grease to stop it happening again not just add oil.

Oil is good preventative (not as good as grease) but won't cure them if they're really bad.

Originally Posted by fizzwheel

Allan - what exactly is the problem with your bike you are trying to fix ?

Its quite possible that the mechanic that did your service checked all those things, but then its also quite possible that he didnt... depends how much you trust the mechanic that did the work.

Well before, my bike wouldn't start at all like in the vid I posted
(http://www.youtube.com/watch?v=N3ca7HAx3bo)

But now that it seems to be getting warmer, it will tick over, but then the revs just shoot way up, and drop all the way down, no matter if I throttle or the choke is on. If I try again, it either
1- Starts fine with the choke on, choke works this time
2- Same thing, revs go up and then stop
3- As in video, doesn't tick over at all

To be honest, I plan on just waiting until it's warmer, and seeing if that changes, and either way, going on a ride-out, where I'm surrounded by much more knowledgeable people that myself, and probably my mechanic (in terms of SV's) and hoping it happens so I can show everyone.