What the f!@?! is wrong with my bike!? (Honda GB) [Archive]

sammcj

31st October 2009, 14:43

OK So I've made a few post on KB about some issues I've had with my 1986 Honda GB before, mainly to do with loss of power and bad idle / 'popping and stopping'.

So far, I've had 3 people look over it, mainly KG Motorcycles here in CHCH, no one can find the fault!

It randomly pop's and stops, you hear air making a popping noise somewhere and the RPM drops about 1000, this only occurs on idle however I do have a feeling there is some power missing from the engine.

It was a 500cc and was bored out to 600cc, it did pop and stop before the bore but it is worse now, probably due to the extra bore size.

KG has replaced:

-The carb
-The Ignition / CDI
-The generator
-Checked over wiring (but he's probably not very good at that!)
-Replaced muffler with a more free flowing one
-Valve clearances are good (thanks to help from T.W.R.!)
-Disconnected battery and checked charging rate
-Replaced coil under clutch cover (can't remember the name of it)
-Pretty sure there are no air leaks coming into carb
-Carb has been fully disassembled twice and checked over.
-Carb re-jetted
-Spark plug and gap is fine
-no airbox obstruction
-It's noticeably worse when it's hot.
-I have seen the indicators go to fast as if there was a blown bulb at times.

The head was leaking a bit of oil around the seal and KG put a new gasket on it yesterday, also did an oil change - after this it's running much worse today than it ever has.
KG motorcycles has spent countless hours trying to fix this and now doesn't want to see the bike again and to be honest I've lost all faith with them!

I've uploaded a video to youtube of it doing it REALLY badly (After the CHCH ACC ride today)

If you're the one that has the right solution for it I'll buy you some beers! :beer::beer::beer:

Here is the video:

http://www.youtube.com/watch_private?v=Il84EYkAT5E&sharing_token=AkrigE_6yhyfgYGywBApKg==

nothingflash

31st October 2009, 15:07

I wouldn't know the difference between a piston and a piss take but I do wonder how many here will reply to say the first thing wrong with it is it's a Honda?

bsasuper

31st October 2009, 15:12

Checked for any airbox obstruction?

sammcj

31st October 2009, 15:14

Checked for any airbox obstruction?

Thanks for the reply, yes I have, I've even removed the (new) airfilter and left it idling with the side cover off to test. Didn't make a difference.

dino3310

31st October 2009, 15:27

..choke...

sammcj

31st October 2009, 15:28

..choke...

Idles OK with the choke on, but it does if you hold the throttle on too!

sammcj

31st October 2009, 15:33

It's noticeably worse when it's hot.
and I have seen the indicators go to fast as if there was a blown bulb at times.

dino3310

31st October 2009, 15:37

dino3310

31st October 2009, 15:40

It's noticeably worse when it's hot.
and I have seen the indicators go to fast as if there was a blown bulb at times.

sounds like the leckys mate, which i know F all about.
sounds like these KG chaps have got there heads up there .......,

sammcj

31st October 2009, 15:43

i had a 650 that was poppin and stoppin all the time speacially while engine breaking or backing of fast from the revs she'd just stop, turned out the choke was slightly jammed on, only got dail up so cant watch youtube to compare, hope you get it sorted mate

hmm interesting...

how do you go about adjusting the choke, do you remove the grip etc...?

I just pulled the sleeve off where the choke cable enters the carb, the cable is loose enough that I can pull on it and see the metal end to the casing...

(hope you can understand what I mean... could upload photo)

sammcj

31st October 2009, 15:50

I can push the metal end of the cable down into where it sits in the carb but how does it stay there? surely the rubber casing can't keep it in tight?

sammcj

31st October 2009, 16:07

hmmm this choke thing could be a go-er. I just made sure it was really securly seated at the carb end, did run fine BUT that could be because it's not hot enough to fault again.

On the chch ACC ride today I was constantly battling to keep the bugger running at the lights, I find I can combat the 'pop' by giving it a little gass and it keep running, prob is when it's popping almost constantly on idle.

Hmmm... choke.... hmmm...

R1madness

31st October 2009, 16:23

Ring my shop on monday, (number at the bottom) talk to Roger. Book it in and it will come out fixed.

sammcj

31st October 2009, 16:26

Ring my shop on monday, (number at the bottom) talk to Roger. Book it in and it will come out fixed.

Thanks, I'm a bit broke at the moment after taking it to KG to get the head retentioned which resulted in a head bolt snapping ($350 later), I'll look into this if I don't have it resolved soon.

laserracer

31st October 2009, 16:27

sammcj

31st October 2009, 16:30

is the choke cable mybe seized inside the outer ??we just had a problem with a seized hot start lever that had the same symptoms it also looked very much like your choke cable .. have you tried undoing the plastic nut and trying to free the cable ??

Good plan, pretty sure KG replaced it with a new one during the bore out to 600 due to them melting it against the engine fins :bash:

How tight is the end of the cable outter (the metal part) meant to sit in the carb? i.e. should it take much effort to pull it out exposing the cable going into the plastic nut?

Henk

31st October 2009, 17:53

Not sure if this will help, haven't seen the video but, had a TTR600 a few years back that started missing and backfiring like a bastard. Did this at any revs, turned out the wiring where it came out of the CDI had worn through the insulation and vibration would run it into the frame and cause the miss. With everything you've already done I'd be having a look at the leckies to see if you don't have an intermittent short.

laserracer

31st October 2009, 18:45

Good plan, pretty sure KG replaced it with a new one during the bore out to 600 due to them melting it against the engine fins :bash:

How tight is the end of the cable outter (the metal part) meant to sit in the carb? i.e. should it take much effort to pull it out exposing the cable going into the plastic nut?

ours was really loose because the piston/plunger was stuck in its housing in the carb and the spring wasnt doing its job properly,when fixed you could still pull it out of the nut but it was under tension

sammcj

1st November 2009, 12:16

OK, I took the tank, headlight, battery all off and checked over the wiring.

-I noticed the plastic connector that plugs into the headlight bulb is quite melted, I'm wondering if it's arking across the points?... this might be debunked by the fact it still has the same issue when the headlight is turned off.

-After checking the fuse box I found one of the 10A fuses to be blown... but it wasn't for the headlight, the original gb service manual doesn't list what each fuse connects to, the fuse in question is on the far right hand side.

-I pushed the choke cable firmly into the carb and rode into town, ran fine when the bike was cold, idled at 1200rpm at the lights without choke... got about 4 - 5KM away from my house and it started stall at low rpm again, by the time I filled up with gass and stated riding home it was running like a real dog in the lows, coming up to lights at <300RPM she shakes around while you hear her spitting out air.

vagrant

1st November 2009, 12:53

It does sound like a choke issue.
My fireblade started running very rough and missing at idle after I had loaned it to a friend. I have never needed to use the choke, and I know the cable is stuffed. He tried to used it, got it part open and the cable broke, so he pushed the end back in, but it did not close the choke properly, hence over rich running at low throttle openings. He just wound the idle screw down a bit to cover it. Also forgot to mention the broken cable.:bash:

jellywrestler

1st November 2009, 12:56

maybe the coil or cdi is breaking down when hot???

laserracer

1st November 2009, 14:36

have you checked the petrol cap vent hole it might be blocked when it starts to play up try taking off the petrol cap and see if it makes a difference

roadracingoldfart

2nd November 2009, 06:28

OK So I've made a few post on KB about some issues I've had with my 1986 Honda GB before, mainly to do with loss of power and bad idle / 'popping and stopping'.

So far, I've had 3 people look over it, mainly KG Motorcycles here in CHCH, no one can find the fault!

It randomly pop's and stops, you hear air making a popping noise somewhere and the RPM drops about 1000, this only occurs on idle however I do have a feeling there is some power missing from the engine.

It was a 500cc and was bored out to 600cc, it did pop and stop before the bore but it is worse now, probably due to the extra bore size.

KG has replaced:
-The carb
-The Ignition / CDI
-The generator
-Checked over wiring (but he's probably not very good at that!)
-Replaced muffler with a more free flowing one
-Valve clearances are good (thanks to help from T.W.R.!)
-Disconnected battery and checked charging rate
-Replaced coil under clutch cover (can't remember the name of it)
-Pretty sure there are no air leaks coming into carb
-Carb has been fully disassembled twice and checked over.
-Carb re-jetted
-Spark plug and gap is fine
-no airbox obstruction
-It's noticeably worse when it's hot.
-I have seen the indicators go to fast as if there was a blown bulb at times.

The head was leaking a bit of oil around the seal and KG put a new gasket on it yesterday, also did an oil change - after this it's running much worse today than it ever has.
KG motorcycles has spent countless hours trying to fix this and now doesn't want to see the bike again and to be honest I've lost all faith with them!

I've uploaded a video to youtube of it doing it REALLY badly (After the CHCH ACC ride today)

If you're the one that has the right solution for it I'll buy you some beers! :beer::beer::beer:

Here is the video (youtube is processing it now so it might take a moment to appear).

http://www.youtube.com/watch?v=Il84EYkAT5E

Check the decompression valve on the r/h side of the head . If you hear a popping sound it could be a case of it not seating and that will give you a compression leak out the pipe.
The semi melted plug bit is just common , check the regulator rectifier for values.
The GB range of bikes are very very fussy on thier tappit settings so even though you say they are set , are they set properly ?
When they first came out i and all Honda techs used to pull large amounts of hair out trying to get them sussed after the first service , it all came down to valves and air flow / leak issues.

Cheers Paul.

sammcj

2nd November 2009, 08:06

OK, thank you all very much for your input, much appreciated!

Are the tappet settings the same as valve clearances? (Sorry I'm pretty new to this)

Tonight / Tomorrow Night I'll Be Checking The Following:

-Decompression Valve / Lever

-Valve Clearances (again)

-Petrol Tank Vent

-Choke cable possibly not working correctly (I found from the manual the needle is supposed to poke out 10-20mm)

MSTRS

2nd November 2009, 08:37

Check the decompression valve on the r/h side of the head .

This would be a priority check for me too.
The problems you have seem to be 'hot' issues, which strongly suggest expansion problems with area/s that that have critical tolerances.
I doubt the melted h/light plug is involved - that is a separate issue.
Also not likely to be a coil...they fail under load, not at idle.

laserracer

4th November 2009, 13:25

So how did you get on ??????

sammcj

4th November 2009, 13:27

So how did you get on ??????

ugh i've been bogged down a bit sick, spoke to kg asking if he'd fiddled with anything that could have made it worse, he said it could be the o-ring coming into the carb, im going to pop by and have a look at it with him tomorrow (he's not charging as it may be his fault)

I'll let you know asap!

CookMySock

4th November 2009, 14:16

sammcj

4th November 2009, 14:19

I actually wonder if its running real real lean - that will make it pop and backfire when ridden anything but very lightly. Is the exhaust sooty and black? Is there any blueing on the exhaust near the cylinder? Try starting it from dead cold (first start of the day) with no choke - if its too lean it will be fooken hard to get going.

Steve

Exhaust is quite sooty & black.
Backfires on revving down (i.e. coming up to lights / stop)
There is no way you'd get it started from cold without the choke.

AllanB

4th November 2009, 14:34

Check the plug and see what it looks like - it will tell you if it is lean or rich. Also make sure they have the correct plug in there - it may be the wrong heat setting. Lean will pop on decel and if it is mega rich (I doubt as you probably not need choke then) maybe it's unburnt fuel igniting.

Cable - even if it is new it may be obstructed somewhere under the tank when you turn the bars and thus gets pulled slightly open. If in doubt remove it and reroute it on the outside where it is 100% free of any obstructions (use a bit of duct tape to hold it temporarily in place against the tank or frame if necessary) - does this make a difference?

Carb rubber - the rubber between the head and carb and or carb and airbox - they may have holes and be leaking. A check apparently is to spray them with WD40, run the bike and look for bubbles or holes in the oil coating.

Alternatively buy a Suzuki - at least you'll expect problems then ..... :bash:

grotto

4th November 2009, 16:01

I had a similar problem with my GB which was choke related. I took the choke cable out of the choke lever, and it was fine. I ended up making a new inner for the choke cable and re-fitting it. I think the old one was a bit short.
Have you checked the inlet manifold isn't leaking? I also had that with mine.
Good luck, and nice bike, worth sorting out, although it sounds like you've soent a fortune trying to get it fixed already

sammcj

5th November 2009, 19:37

OK so...

I left the bike at KG today, he wanted to have a look at it before I go pulling things much further apart.

Came back to it and took it for a spin, seems to be all good!
Trotted back to KG to ask what he'd done turns out he's not 100% sure what actually fixed it. (It still pops at times, but it's manageable)
He said all he did was adjust the idle mixture screw on the bottom of at carb, which he has adjusted before and did not touch when he did the head recently.
The weird thing is, he recons he only screwed it all the way in, then back out to roughly where it was!
He said he may have knocked the choke cable but he checked that and he thinks the cable is fine (mind you he did make it up so might be trying to cover his ass?)
ANYWAY

As for the blinckers flashing too fast when under rev's that was due to him(?) mistakenly putting one bulb in that was the wrong wattage!

Took her for a scream at the port hill to watch the sunset and she went well, didn't stall on me once, is definitely lacking a bit of power perhaps due to the crappy stock pipes.

So I guess it's good and bad news, the good is it's fixed - the bad is that we still aren't 100% sure what was wrong.

I'm going to keep and eye on it and see how it goes.
Next step: Tighten up the steering a bit, replace front lamp and break shoes.

Thank you all for your input and advice, I'm sure you be using it when this happens again in the future (not doubt you'll hear about it!).

-Sam.

dino3310

5th November 2009, 21:49

on ya mate :niceone:

laserracer

6th November 2009, 05:44

Sweet... glad its seems to be fixed :woohoo:

sammcj

6th November 2009, 16:23

CookMySock

6th November 2009, 16:32

he recons he only screwed it all the way in, then back out to roughly where it was!If there was some shit in the the idle jet, that might clear it out.

Steve

xwhatsit

6th November 2009, 16:57

Little update:

Just went out and gave her a bit of shit in the countryside.
She popped once after pushing it up a straight then coming to a stop - I'm not too worried about this.

She's definitly lacking some power, it was actually somewhat better when it was running worse.

-There is big, disappointing _nothing_ between 6 - 8k RPM.
-It took roughly 4 seconds from sitting at 80Km to speed up to 100Km in 3rd gear.

Bit of a shame, mechanic said she'd really fly as a 600 but it seems slower than a factory 500 (except perhaps at the low-end, FYI Factory 500cc 0-60 is 5.4s)

If I had more money to throw at it I'd probably get another set of headers and take it somewhere else for a tune-up, but being a part-time student I'm out of luck there so I'll keep on plodding along with it as is I guess, I was hoping to take her down to Oturehua later this month but I don't think I'd trust her.
So you bored out a big single a large amount (I remember reading you upped compression a good whack as well?) and now it doesn't idle well... hmmm....

I know it's a common modification on the RFVC engines but still, it's not exactly world-shattering to end up with those results.

Having flat spots in your rev range is surely an issue of inappropriate carburettion for the capacity increase. Put the fiddly CV carb away, get hold of a big simple slide carb that's of appropriate size (probably 2mm smaller or the same size as the existing CV carb?) that's easy to tune and have it put on a dyno by somebody with plenty of needles and jets. May even find the recalcitrant idling improves!

Automatic decompressors are an accident waiting to happen. I've got a generation older single than yours but my decompressor has caused exhaust valves to stay open when starting (where's all my compression gone!) and in other circumstances refused to work properly so I took the little cam on the kickstarter out. Simply roll the bike backwards in first gear til TDC before kicking. The RFVC decompressor might be very reliable but it's still another variable.

However, intake leak would cause all of those problems (idling, flatspots, poor general performance). I assume somebody's sprayed carb cleaner all around the intake manifold joints while it's running to see if the engine does anything?

sammcj

6th November 2009, 17:03

So you bored out a big single a large amount (I remember reading you upped compression a good whack as well?) and now it doesn't idle well... hmmm....

Actually I didn't up the compression.

Put the fiddly CV carb away, get hold of a big simple slide carb that's of appropriate size (probably 2mm smaller or the same size as the existing CV carb?)

Who do you think I should speak to about procuring / fitting?

Automatic decompressors are an accident waiting to happen.
hmm I might just do this!

I assume somebody's sprayed carb cleaner all around the intake manifold joints while it's running to see if the engine does anything?

I'm not sure what KG did, put it this way... I wouldn't trust that he did.

Ixion

6th November 2009, 17:04

Well, actually you DID up the compression, By quite a lot, unless you relieved the head.

sammcj

6th November 2009, 17:12

Oh really, didn't realise it worked like that, Shows how much I know about engines.

xwhatsit

6th November 2009, 18:59

Who do you think I should speak to about procuring / fitting?

Something like a Mikuni VM-series (VM48 too big?) could be ordered from a myriad of sources on teh interweb cheaply. Fitting it is something you could do at home very easily; may need to have a new throttle cable made up (then again the VM is cable-pull like a CV carb, wonder if you could get away with the same cable end) and perhaps a bit of swearing getting the intake manifold to fit over the carb stub but nothing a complete bodger like the average KBer couldn't handle.

I'm not sure what KG did, put it this way... I wouldn't trust that he did.
You can do that at home. Buy a can of carb cleaner, get the engine warmed up, spray liberal amounts on the interface between head and manifold and manifold and carb (less likely). If there's any change in engine note (the engine might pick up or suddenly miss or even stop -- you may see bubbles as the carb cleaner gets sucked in) then you have a leak. Go right around, check on both sides of the bike. You might like to try it with a bit of RPM too.

You might be able to tune the stock carb to match the increase in bore, but a simple slide carb is very easy to tune comparably. Surely the best thing is to get it onto a dyno once you've checked everything else (the valve clearances sound interesting, had no idea they could cause trouble like that), either with the stock carb or a new one, and get a proper expert to look at it under load.

Mebbe you could flog a carb off a Dommie, that might match well with minimal fiddling?

sammcj

25th November 2009, 08:01

Right, Got her booked in at Dynoworx / HondaCountry next wednesday.
I'll let you all know how the dyno-tune goes!

sammcj

1st December 2009, 17:12

I'll be at Dynoworx Ashburton tomorrow at 9AM... Wish me (/ my wallet?) luck

dino3310

1st December 2009, 19:09

:niceone: we'l be waiting in anticapation of the out come :clap:

sammcj

1st December 2009, 19:11

:niceone: we'l be waiting in anticapation of the out come :clap:

if there is one thing you can count on, it's that I will
be posting my results on kb! (talk about making or breaking their business!)

T.W.R

1st December 2009, 19:35

:laugh: You've got a PM :shifty:

sammcj

1st December 2009, 20:29

:laugh: You've got a PM :shifty:

Now you've got me all worried about tomorrow!
Hopefully they're good bastards and good a good job for their money :Punk:

I've had a few bet's from other KB'ers that the result will be good but we'll see!

Kickaha

1st December 2009, 20:35

Now you've got me all worried about tomorrow!
Hopefully they're good bastards and good a good job for their money :Punk:

I've had a few bet's from other KB'ers that the result will be good but we'll see!

You got nothing to worry about

I rate them quite highly on the "good bastard " scale and so do a few others I know who have used them

I would have bet you everything you own but I would have felt guilty about taking it all off you

sammcj

1st December 2009, 20:39

I would have bet you everything you own but I would have felt guilty about taking it all off you

haha thank you for the reassurance. I sure hope so; this bloody bike's been a headache, can't say I haven't learnt a thing or two though!

One thing I did like about them is that when I asked if I could hang round while they were working on it, the mechanic was more than happy I mentioned I was going to take a few photos to chuck on the net!

T.W.R

1st December 2009, 21:26

Now you've got me all worried about tomorrow!
Hopefully they're good bastards and good a good job for their money :Punk:

I've had a few bet's from other KB'ers that the result will be good but we'll see!

:bleh: nah you've nothing to worry about with the quality of their worksmanship :niceone: the guy who does most of the dyno work know his stuff.
The crew there are some of the better mechs for modern stuff in Ashvagas

izzyc

1st December 2009, 21:33

I had a mate with a similar problem....check that the fuel tank breather holes are completly clean and clear....once he cleared the breather holes were clean the bike went a shitload better......[being blocked causes a vaccume effect on the fuel system and makes it look like an electrical problem]

sammcj

2nd December 2009, 12:55

Alright, I'm Back…

Where do I even begin?
I have to start by saying I could not possibly be more impressed with Honda Country / Dynoworx than I am, They were in a word… brilliant! Very honest, Fast working, clearly very clued up and at no point tried to 'up-sell me'.

They strapped her up on the Dyno and we went to do the first / base run… BUT it was running so damn Lean it wasn't even safe to push it (Yeah… Thanks for that KG Motorcycles…)

So off came the carb, They decided to go 4 sizes up with the jet.
Here comes the second run… WOW WTF IT'S WORSE?!
Off comes the carb again…

Turns out KG Motorcycles had replaced the jet with one he had drilled out and never scratched the label size off!

This time they put a main size of 158 in and back on the Dyno.
Talk about hit and win… The bloody thing nearly took off!
Some small adjustments to the idle mixture and up for the last run…
Came out just shy of 32BHP so we're guessing it'd be around 36-37HP at the flywheel.

Took it for a spin up the road and all I can say is Wholly Shitballs!
It's running A) Smoother than has ever run. B) Feels like it has around 40-50% more power!

I have to give a 1-Up to the guys there, they were really great and didn't at all mind explaining things along the way, they even replaced some old hoses and adjusted my chain for me while I was getting ready to head off, also the cost really isn't really much at all - definitely worth the benefits.

SUCCESS!

(I owe a round to some of you guys for pushing me to do this.)

:done:

[Little update at 6.45PM - Just got to take her out now it's dry - VERY impressed, she has power right through the rev's, very responsive and boy is she smooth!]

MSTRS

2nd December 2009, 13:01

Turns out KG Motorcycles had replaced the jet with one he had drilled out and never scratched the label size off!

I hate that!! Cheap, lazy bastards. Causes no end of trouble for those down the line.
Glad you are sorted.

JKM

2nd December 2009, 17:07

Congratulations on that!! You'll be pleased to finally reach some of that potential power!!

Are you happy with it now, or is there still more work on the horizon?

sammcj

2nd December 2009, 17:18

Congratulations on that!! You'll be pleased to finally reach some of that potential power!!

Are you happy with it now, or is there still more work on the horizon?

Thanks mate!

Well I'm pretty damn happy with how it's running.

Next I need to:

-Slightly re-shape front mud guard
-Do fork oil
-Replace cracked headlight

In the future I plan to replace the exhaust system completely.

dino3310

2nd December 2009, 20:09

awesome bro good to see you back up to boogie:niceone:

crazyhorse

3rd December 2009, 07:31

Good on you - at least you'll be out riding soon - if winter actually goes away grrr!

sammcj

10th December 2009, 17:05

Kickaha

10th December 2009, 17:10

Slight problem:

Just looked at the factory specs for the 500cc and compaired it to my 600cc after the dyno and guess what...

My 600cc is putting out 31.5BHP but the factory 500cc puts out 33.3BHP on the dyno and 38HP at the flywheel!
Something can't be right, Obviously it's running better than it was before the dyno but WTF!?

http://www.motorcyclespecs.co.za/model/Honda/honda_gb500_tourist_trophy.htm

Dont waste your time comparing different dyno specs for a start, you could run that bike on 6 different dynos and get 6 different figures

As long as it's going ok and you're happy with it HP figures are meaningless

sammcj

10th December 2009, 17:11

Dont waste your time comparing different dyno specs for a start, you could run that bike on 6 different dynos and get 6 different figures,yours is also rear wheel Hp the factory quoted spec is most likely at the crank

the 38hp is at the crank, but the 33 was of a stock 500cc.

I took her out for a spin yesterday and I SWEAR she was far more guttless than shes been since the dyno.

T.W.R

10th December 2009, 17:46

the 38hp is at the crank, but the 33 was on the dyno of a stock 500cc.

I took her out for a spin yesterday and I SWEAR she was far more guttless than shes been since the dyno.

.........:whistle:

sammcj

10th December 2009, 17:54

.........:whistle:

Hmm... is it possible those tappets could have self adjusted?
After we adjusted them that time when I took it back to KG he said he had to space them out a bit as he couldn't move them at all?

:baby:

She was really REALLY good after the Dyno, since then I've done perhaps 200KM?

What could have self-adjusted since then...?

Kickaha

10th December 2009, 18:14

I took her out for a spin yesterday and I SWEAR she was far more guttless than shes been since the dyno.

More likely you have just got used to it

sammcj

10th December 2009, 18:18

More likely you have just got used to it

I considered that, feels like shes running out of steam a bit... oh well...

Think I really need to save up and get a sports bike ;)

T.W.R

10th December 2009, 19:38

Hmm... is it possible those tappets could have self adjusted?
After we adjusted them that time when I took it back to KG he said he had to space them out a bit as he couldn't move them at all?

:baby:

She was really REALLY good after the Dyno, since then I've done perhaps 200KM?

What could have self-adjusted since then...?

After the bollocks he put you through are you really going to listen to his woffle?

you saw what was done, how it was done and what the specs for the clearances were and what they were set at with your own eyes.

Take the plug out & lets see what colour she's burning :blink:

sammcj

11th December 2009, 13:47

After the bollocks he put you through are you really going to listen to his woffle?

you saw what was done, how it was done and what the specs for the clearances were and what they were set at with your own eyes.

Take the plug out & lets see what colour she's burning :blink:

Yeah I know, still though... Seemed to go alright on the way to work this morning.

I'll check out the plug this weekend, mixture should be mint unless the bike fairy has been tinkering with my carbie over night ;)

I've got to get a new front guard made up too - perhaps Santa will bring me one if I ask him nicely. :eek:

T.W.R

11th December 2009, 14:09

I'll check out the plug this weekend, mixture should be mint unless the bike fairy has been tinkering with my carbie over night ;)

Got nothing to do with whats happening with the carb mixture unless you've been a Harry Ham-Fist whilst you've been riding it.... :wacko:

post a piccy of the plug when you've got it out

sammcj

11th December 2009, 14:50

unless you've been a Harry Ham-Fist whilst you've been riding it.... :wacko:

hah well I probably do ride it a bit 'harder' than it was indented to be ridden. :Punk:

T.W.R

11th December 2009, 15:04

hah well I probably do ride it a bit 'harder' than it was indented to be ridden. :Punk:

:lol: you been sniffing the exhaust fumes again ?

sammcj

11th December 2009, 15:07

:lol: you been sniffing the exhaust fumes again ?

Getting a much 'richer' hit after the the tune-up :eek::eek:

sammcj

12th December 2009, 11:18

Take the plug out & lets see what colour she's burning

Plug: DPR8EIX-9

It's about 4 months old so it was in there when the bike was running lean.

Gap:
about 0.65mm

Colour:

Black around the very top where the tread ends.
VERY white on the Side Electrode
Center Electrode is clean

sammcj

12th December 2009, 11:45

Adjusted Gap to 0.85-0.90mm as per GB500 Manual.

I'm guessing it was so white because of how lean it was before the tune-up.

T.W.R

12th December 2009, 13:10

Colour looks pretty good but possibly a bit of insulator glazing.... so if that being the means there's been a sudden rise in plug temp during use which would concurr with the slight mis-fire you've mentioned before. If you've got a standard plug go to the next heat range 8 to a 9 (colder)

:lol: you don't screw around with the gap on an Iridium plug :nono:

sammcj

12th December 2009, 13:12

Yeah that pretty much co-insides with what I've read.

:lol: you don't screw around with the gap on an Iridium plug :nono:

:Oops:

enth

13th December 2009, 20:55

Haven't read through all the posts but I thought I'd put in my two cents seeing as though I really like your bike :niceone:

Maybe there is slight dent/dip in one of the cylinders? If it's super small no one would notice it and bike could still run?

I could be totally wrong though.

sammcj

14th December 2009, 09:19

Input is always appreciated!

Well it is now a lot better than it was but... is there any way I could prove / disprove this?

enth

15th December 2009, 21:42

You would probably have to take the pistons out and have a look inside the cylinder for where it's not rubbing. But to be honest I wouldn't bother unless you had a whole weekend spare to mess around with it.

But if you say it's better then I'm most likely wrong and you shouldn't take my advice :P

koba

15th December 2009, 21:57

Input is always appreciated!

Well it is now a lot better than it was but... is there any way I could prove / disprove this?

How was it made bigger? Oversize liners can bulge and have all sorts of problems.

as for the plug reading, forget it, thats what the dyno runs were for.

any readings on old plugs are useless anyway, if you wan't to have a looksie (not a touchie) at the plug try it with a new one and pull it after a bit of running but do remember it is only a guide to how hot it is running and no where near as good as a proper dyno tune.

Also check your chain, the dyno curves look like they may have been run with a fucked chain, they have a quite a sawtooth pattern to them.