What's up with my RF [Archive]

riffer

21st November 2006, 07:58

It started doing funny stuff on the way to work while following Fat Jim on his Bayliss Ducati.

It's only running on three cylinders until it gets to about 5,000 rpm then it goes on to all four.

It's a bit like when it was getting water in the coils and low tension leads.

Weird. Any ideas on how I can go about diagnosing it?

Grahameeboy

21st November 2006, 08:01

Have you changed to higher octane recently.....or maybe it is trying to be a v-twin cause wants to sound like a Ducati........my RF changed into an SV

MSTRS

21st November 2006, 08:12

First, find out which cylinder is affected (bike shop will have a heat sensor that reads the headers). After that....????

riffer

21st November 2006, 08:18

Interesting. I was leaning more towards maybe a valve dropping, but I'm not sure as it seems to go allright when it revs up.

I filled up at Pak N'Save yesterday morning and I've done about 80kms before the problem started.

Fatjim

21st November 2006, 08:19

Ah, so thats your excuse. I had to wait ages for you to catch up!

You weren't doing too badly from the Lower hutt lights! Man I love it when the front is only planted when your changing gear.

riffer

21st November 2006, 08:21

Postie

21st November 2006, 08:21

Have you tried the simple things, like checking the plugs and coils/coil leads?

erik

21st November 2006, 08:49

First, find out which cylinder is affected (bike shop will have a heat sensor that reads the headers). After that....????
you can just touch a wet rag to each header and see which one doesn't hiss.

Motu

21st November 2006, 09:24

Plugs and/or leads.

terbang

21st November 2006, 09:33

Fatjim

21st November 2006, 11:01

Don't we have a resident sparkplug lead sucking expert somewhere round here?

Fatjim

21st November 2006, 11:04

Yeah, I'm blaming you mate for the bike problems ;)

Damn that 998 is quick.

The needle on the speedo was about 5° past vertical catching up with you.

RF owners will know how fast I was going on the 190mph speedo. :innocent:

Imagine what the duc would go like with someone who doesn't weigh more than the Cook Strait Ferry!

Anyone want to buy a shiny 998s?

Shaun

21st November 2006, 11:52

Put your hands on the Header pipes whilst it is running, which ever is cold is the culprit

Pull that plug and change with another cyclinder, that will awnser if it is a faulty plug or not

riffer

21st November 2006, 12:16

Thanks for the advice Shaun.

Just did it, and dammit! The problem's gone away! :angry:

Obviously an intermittent fault.

Oh well, I need a night in the gargre. Things are just going a little too well lately (haven't been threatened with being kicked out of the house for at least a week :dodge:)

MSTRS

21st November 2006, 12:19

Check your plug cap (s). Had a similar problem on the 1100 and it was the retaining clip in one of the caps - was missing, meaning that the top of the plug only made intermittent contact with the business part of the cap.

emaN

21st November 2006, 12:46

looks like erik & shaun are onto it...
hope you get it sorted bro...

(i'll check that "5 degrees past vertical" tonight:shifty: )

F5 Dave

21st November 2006, 16:51

Suzukis GSXRs & Derivatives do have issues with coils, but pull the plugs & check if any look like they are considerably blacker than the others. Here is a bad picture of an emulsion tube I pulled out of my RF a couple of weeks back.

What you can see if you squint & imagine it after I've subliminally suggested it through mind damaging thought control (sorry:innocent:) is it is ovalised & can even see swarf.

riffer

21st November 2006, 20:01

I've been on the phone to Frosty tonight, and gradually pulling the bike apart and testing things.

Not the plugs.
Not the coils.
Not the low tension leads.
Not the high tension leads.
Not any gunk in the float bowl either.

Here's the problem. And I didn't work it out until I decided I was going to have to strip number 1 carb and blow out the pilot jet, which both Frosty and I decided was the problem.

And I pulled off the airbox, and blow me down, there's something rattling around in it. It drops to the ground and looks suspiciously like a javelin head. Bugger me, that's gotta be a jet needle, says I.

And wouldn't you know it. The bloody jet needle's broken off in number 1 carbie and most of it (I hope) has found its way into the airbox.

Check out the pics. Father in Law will be pillioning me to work tomorrow.

Now I've NEVER heard of this happening before. But I stand ready to be corrected on this.

Motu

21st November 2006, 20:53

I've never seen a needle break either,there is just no stress on them in that direction to cause a break.So either at some point in time it has undergone some stress in that plane,or there is a manufacturing fault.

Ixion

21st November 2006, 21:33

I've seen it. Only once . There is stress on them the air flow past them can actually induce some considerable stresses, under certain circumstances they can actually vibrate

Motu

21st November 2006, 21:43

Yes,could certainly do that.When SU got rid of the fixed needle and went to a floppy floating needle there was some jet wear,they would make the jet oval.So if the needle didn't have enough spring tension on it it could set up a vibration, a certain frequency could induce a failure for sure.

riffer

21st November 2006, 22:03

What you can't see from the photos is the wear on the needle.

Looking sideways at the end that was still stuck in the diaphragm, you can see that there's been some wearing and its actually nearly worn to half its diameter on one side. I'm thinking that the gradual wear of the needle going up down the emulsion tube has caused it to fail right at the point where the wear stopped as there's a clean break there.

So, I can get a new needle, but its got me wondering. The RF's have a reputation for ovalising their emulsion tubes (if that's what I think they are - looking at the service manual Suzuki call it a needle jet). Is it possible that worn emulsion tubes would cause this kind of wear?

Damn. Its 11.00 and too late to go back out to the gargre but I really want to pull the diaphragm caps off the other carbies and have a damn good look at the needles on those as well...

Something for tomorrow. I wonder if Wellington Motorcycles will have a new jet needle in stock...

Fatjim

21st November 2006, 22:11

Another farkin suxuki craps itself while following a Ducati!

Glad it's sorted mate. That is one pain in the arse fault.

May be cheaper to get a dynojet rejetting kit, probably a good idea to do all the carbies at the same time.

Ixion

21st November 2006, 22:15

The needle moves in the needle jet (aka emulsion tube) . The movement wears the jet. But obviously if the needle rubbing on the jet wears the latter, the needle must also wear.

So it is likely that all the needles and all the jets are worn. Replacement should improve fuel economy , engine smoothness and maybe power.

riffer

21st November 2006, 22:27

Engine Smoothness? :rofl:

You've never ridden an RF have you Ixion?

Actually, it's been a bit rougher than usual lately. I guess its just sneaked up on me.

Money, as usual, will be the final arbiter on this one. This close to Xmas I'm betting it will be the replacement of the needle unfortunately.

I'll put the full rejet on the to-do list. Actually, F5 Dave - you've just done this - what's the damage for all four carbies?

Motu

21st November 2006, 22:47

How loose are the needles? If you can find some way to firm up their seating they may not move around enough to contact the needle jet (the more common term for this part) After all there have been millions upon millions of bikes that haven't had this sort of wear....something is wrong with the initial design - rectify Suzuki's fuck up.

Ixion

21st November 2006, 22:51

Thing is, if you lock 'em down, you're going to have to make sure they're centralised in the jet, and in exactly the same plane. I suspect this is why they are designed loose, so Suzuki (OK, Mikuni or whoever) didn't need to worry about getting them concentric with the jet.

riffer

22nd November 2006, 07:30

Well, I showed the needle to the head mechanic at WMCC (can't remember his name). He says he's seen it before in RFs.

His explanation is it's caused by negative/positive air pressure in the carb causing the needle to go back and forth while going up and down. Apparently there's some kind of design problem in this carb that causes the needle to flutter a bit.

Motu

22nd November 2006, 08:24

Apparently there's some kind of design problem in this carb .

And like how many millions of carbs has this company designed and produced without any problems of this sort? They must of given the job to some kid fresh out of design school - all those old guys didn't know what they were doing huh?

F5 Dave

22nd November 2006, 08:25

I have some spare needles you can have, erm, somewhere, I'm shifting this weekend so they are in a box, but I think I know which one.

Check the emulsion tube (needle jet sorry) it runs in too as said.

Yams with similar carbs have same issues. Many bikes do, 'parently.

riffer

22nd November 2006, 15:16

Damn. I read this far too late. However, another needle may do the trick until the four new ones I've ordered arrived - chances are, if one's that worn, all of them are.

Mine's the Yank model - what's yours Dave - USA, Canada or Aussie?

As for the needle jets themselves, what do they cost for replacement?

F5 Dave

22nd November 2006, 15:35

E06 model, never really worked out where that was for. kph speedo. There were some Italian ones too I believe. NZ dumping ground of the world. Made them cheap though. My needles were no where that worn, just rubbed on the sides. Bought factory ones.

I bought some tubes from Factory http://factorypro.com for erm, maybe $20US each, Thing to watch for too is the plastic inserts that the slides run on wear. You can hook them out of the carbs once the bottom of the tubes are freed, nothing difficult. But they seem to wear more on the left hand side. Marc from Factory told me has seen this too. Built up mine with araldite, seemed to work ok but not had chance to ride it long enough to strip it apart to check if still ok.

riffer

22nd November 2006, 16:08

And you guessed it, the manual doesn't have the carb specs for the E-06 model.

My carbs use 5DV3 jet needles. What needles have you got spare? Your's probably won't be the same. All the Euro bikes seem to use 112.5 main jets, mine has 120s. I would imagine the jet needles would be a different size to compensate.

F5 Dave

22nd November 2006, 16:10

erm, refer the bit about the boxes. I know the container they are in & I think I know the box. . .
The tube I have on my desk is marked 195K

riffer

22nd November 2006, 20:19

E06 model, never really worked out where that was for.

You know Dave, this got me thinking. So I've grabbed the Suzuki RF900R Service Manual and had a look under General Information.

Here's the country or Area codes:

E-02 England
E-03 USA (except California)
E-04 France
E-15 Finland
E-16 Norway
E-17 Sweden
E-18 Switzerland
E-21 Belgium
E-22 Germany
E-24 Australia
E-25 Netherlands
E-28 Canada
E-33 California (USA)
E-34 Italy
E-39 Austria
E-53 Spain
(E-15, 16 and 17 countries are included in E-22)
(E-21 and 53 countries are included in E-34)

so you've got me a bit confused because according to Suzuki, there ain't no E-06 model. :mellow:

As far as I know, the only models that hit NZ were E-24, E-03 and E-28. But I'm not Suzuki dealer.

F5 Dave

23rd November 2006, 08:11

Pass, it's just a sticker on the headstock. Maybe it is the default & there is another somewhere, actually I think my friends muffler was stamped E06 & his is MPH speedo & faster (a tiny bit) than mine (cams I think).

riffer

24th November 2006, 10:16

Well, I pulled the other needles out yesterday, and they've all got exactly the same amount of wear. Looks like I got to it just in time.

F5 Dave

24th November 2006, 10:36

Boo. How long are the new needles away?

If you need my ones I will probably have found them by sunday.

riffer

24th November 2006, 21:16

Boo. How long are the new needles away?

If you need my ones I will probably have found them by sunday.

Ten miserable bikeless fucking days, minimum.

My only shining lights at present (apart from your offer to borrow your old needles) are that I get to pillion in on the Father-in-laws bike, I have the latest episode in the Dune series to read on the train on the way home, and Pete at WMCC has offered to let me test bikes in the meantime.

And Gini fell over in the shower and stuffed her shoulder so I've spent the last two days at home looking after her and the kids.

I'm turning into a sad miserable old git. At least there's still my guitars...