Carb Chaos

This... *lovely* ZZR 600... This AMAZING bike of mine...

I hate it already.

So, I did something stupid. I was low on fuel before the MOT, so naturally I felt it would be a good idea to fill up a petrol can without checking the contents. It must have had some crap inside because the bike started complaining when going over 65mph, which you can guess how that is on a motorway. The slowdown and sudden acceleration was a little off putting.

It got better with a bit of premium unleaded, but never completely gone.

Yesterday, I pulled the carbs off (after some frantic fun with coolant gushing down my leg) and tried to get the float bowls off, and failed.

Most of the screws are tight af, and it was so bloody hot outside that I just decided to tip the thing upside down to drain it, and stick it back together.

Turned the key and it sprang to life. It revs, sounds ok, so I left it until this morning where I am going to ride 40 miles to work.

Now the issue is far worse and getting above 50mph is a challenge.

The carbs are coming off again, and this time I am going to force my way into the bowls and replace some (about to be) damaged screws.

Before I go full Barry Scott on this thing, does anyone have any wise tips for cleaning carburettors?

Thanks, guys

Strip em and clean em properly, then ultrasonic them. Flush tank out and fuel tap filter.

Eat more protein.

Eat more protein.

I dumped about 1kg of blueberry flavoured protein powder into the tank, so we'll see if that gives it a bit of encouragement to get that needle above 50.

Strip em and clean em properly, then ultrasonic them. Flush tank out and fuel tap filter.

Thanks. I have just had a good look about ultrasonic cleaning, online, but no way can I justify spending the hundreds on the equipment.

I'll strip them down, give them a good scrub, and then would I get away with soaking everything in heated cleaning fluid overnight?

Horribly fiddly job, working on carbs.

There is carb cleaner and there is carb cleaner and then there is the stuff they make for cleaning powerboat engines. I don't know why but it is like carb cleaner on steriods and does a much better job.

Look for Quicksilver Power Tune - expensive but it will clean hardened deposits better than anything else. Johnsons and Evinrude do similar sprays.

With carbs be meticulous about cleanliness and prise things apart gently. They are made of quite soft metal and over the years gaskets stick the bits together so getting them to bits can need some patience.

you may need to balance the carbs after removal

trying to remember if the carb bowls have drain taps .

if so undo and keep tapping bowls whilst flushing fuel through may help .

trying to remember if the carb bowls have drain taps .

if so undo and keep tapping bowls whilst flushing fuel through may help .

I'm pretty sure they do have drains but despite being handed left and right two of the screws appear to face inwards judging by the pics I've seen online.

carb cleaner on steroids advice...

Fantastic. I will try and get my hands on that as soon as I can.

you may need to balance the carbs after removal

Highly likely that I will need to do this. I need to find a half decent kit or learn to do it by ear.

trying to remember if the carb bowls have drain taps .

I think that when I tipped the carbs upside down to drain them (rather than using the correct method that I should have done), whatever crud was lying at the bottom of the bowls got sucked up and lodged somewhere.

I'll re-strip the bike to get the carbs out and get to work. Now, the screws are going to be hard to shift, so may end up having to saw a line through the head of the stuck ones (if possible) to try and turn them with a flat-head driver, because the Philips heads are not getting a good grip on some of them.

Thanks for the great advice so far.

Photos to follow...

re screws ..

dont use posidrive bits .

if you have a multibit screwdriver kit use the standard crossheads

give the bits a few gentle tap into the screws before attempting to turn .and depending on screwdriver type gently tap as you turn

try applying boiling water in the screw area ( pour onto screws localised area ( dont submerge carbs

Now, the screws are going to be hard to shift, so may end up having to saw a line through the head of the stuck ones (if possible) to try and turn them with a flat-head driver, because the Philips heads are not getting a good grip on some of them.

 

This is because the screws on the ZZR are not Philips head. They are JIS, a Japanese standard. Philips will fit but if the screws are very tight the driver will damage the head.

The JIS drivers are a slightly different angle.

http://ruggedroads.co.uk/JIS-Screwdriver-Set-Vessel-Megadora-P1-P2-and-P3

https://www.howtomotorcyclerepair.com/jisscrewdriver/

This is because the screws on the ZZR are not Philips head. They are JIS, a Japanese standard. Philips will fit but if the screws are very tight the driver will damage the head.

I have just learnt something new. Thanks.

New set ordered and on the way.

I never even heard of JIS until now.

Obviously you wouldn't buy a £600 ultrasonic bath. You pay around £100 to get someone else to do it. FFS.

This is because the screws on the ZZR are not Philips head. They are JIS, a Japanese standard. Philips will fit but if the screws are very tight the driver will damage the head.

 

I have just learnt something new. Thanks.

New set ordered and on the way.

I never even heard of JIS until now.

Japanese Industrial Standard in fact . I must admit I mistakenly call everything Phillips . On all my bikes I have always tried to replace absolutely every screw and bolt with an Allen head . It's worth having a look at what Toolstation have to offer but they don't do a full range of lengths .

Obviously you wouldn't buy a £600 ultrasonic bath. You pay around £100 to get someone else to do it. FFS.

Really? I was thinking of pushing the boat out and investing a few grand in a new one to use only once.

Japanese Industrial Standard ... I have always tried to replace absolutely every screw and bolt with an Allen head .

Fantastic suggestion, and is exactly what I'll do. The JIS drivers are on the way and there's a toolstation up the road from me, so will do exactly that if our own little warehouse hasn't got any.

Japanese Industrial Standard in fact . I must admit I mistakenly call everything Phillips . On all my bikes I have always tried to replace absolutely every screw and bolt with an Allen head . It's worth having a look at what Toolstation have to offer but they don't do a full range of lengths .

Was doing that to my GPX.

Sometimes even using the JIS drivers the monkey metal of the original screws caused the heads to shear off instead of just knackering the cross head.

Looking into the JIS v Phillips and found this on a supplier Vessel tools website.

"Vessel Statement on JIS Compatibility:

The Phillips tip of VESSEL screwdrivers is designed with less tolerance than the JIS or ISO standards. Therefore, the VESSEL tip standard is within both the JIS and ISO standards. i.e. it complies with the JIS standard as well as the ISO standard."

Obviously you wouldn't buy a £600 ultrasonic bath. You pay around £100 to get someone else to do it. FFS.

 

Really? I was thinking of pushing the boat out and investing a few grand in a new one to use only once.

 

Japanese Industrial Standard ... I have always tried to replace absolutely every screw and bolt with an Allen head .

 

Fantastic suggestion, and is exactly what I'll do. The JIS drivers are on the way and there's a toolstation up the road from me, so will do exactly that if our own little warehouse hasn't got any.

As I say , Tool station only do a limited range of lengths in their metric SS Allen bolt range so you cannot do , for example, a clutch cover . Nonetheless they are useful for replacing all the short bolts that hold things to the frame etc. I believe they do M4 bolts that could be used on carb tops or float bowls . I'm sure that's where I got mine from .By the way if you do go to TS , their carb cleaner and brake cleaner is well worth grabbing a few cans of , its so cheap you can afford to use it for all kinds of cleaning jobs .

This is because the screws on the ZZR are not Philips head. They are JIS, a Japanese standard. Philips will fit but if the screws are very tight the driver will damage the head.

 

I have just learnt something new. Thanks.

New set ordered and on the way.

I never even heard of JIS until now.

I bet you wish yours came apart as easily as mine ! if you look very carefully you will see that the screws are already dipped in copper slip just in case they have to come apart again. Gloat gloat. You can also see the little piece of guitar string ( high E ) that I used to dislodge the tiny blockage in a pilot jet that was causing me so much grief. See my recent posts in "What did you do to your bike today"

I bet you wish yours came apart as easily as mine ! if you look very carefully you will see that the screws are already dipped in copper slip just in case they have to come apart again. Gloat gloat. You can also see the little piece of guitar string ( high E ) that I used to dislodge the tiny blockage in a pilot jet that was causing me so much grief. See my recent posts in "What did you do to your bike today"

Very helpful mate. Thanks! Bloody good, indeed.

With any luck, the JIS drivers will arrive before the weekend, and I will get my hands on some copper grease. Guitar string shouldn't be a problem - there's a 'Rock Band Guitar' studio next door.

Got a quote back for ultra sonic cleaning - might as well buy a second hand working set of carbs for the prices I'm getting back. Well into the hundreds.

Just been to tool station to get four cans of carb spray and replacement screws.

The bowls came off dead easily with the JIS drivers, so thanks to JRH and you, fastbob for the great advice so far.

A lot of gunk and crap came out of the bowls, mostly on number one. I threaded a thin wire back and forth a few times down the jets, and sprayed cleaner on to make sure that they all began draining at the same pace.

Everything looks much better now and I even took my time to clean the black gunk from the outsides. All is thoroughly, clinically clean.

Next step is putting it all back together.

Well, it works.

The job was a success, and very much grateful as it's an old lump that does not look like a bike that should be on the road, so do not want to spend lots of money on it.

If I can keep it mechanically sound then sod how it looks. It's transport.

First time I tried to start it, it was fuel starved and I heard tricking from under the bike. I only forgot to connect the main feed. Luckily I have small hands, but arms like popeye.

Thanks again for the advice. Just need coolant and I'm good to go.

Road test had no issues.