Thumper Club Forum
Technical => Project Progress => Topic started by: andy230 on September 27, 2006, 10:48:56 AM
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Right then!
After a blatt round cadwell after the annual rally, I laid the skorp up up (or rather, just left it!) for a couple of months. At the weekend I got into welding the frame of the DR. The small crack upon investigation turned into a rotten lower frame tube when I tried to clean it up. Left me with a quarter inch by inch and half gash in the bottom tube. Presumably its sat about for a while on the side-stand, as this would explain the rot from the inside.
Ended up plating it, rather than the inital "quick job" welding over it. The very kind help of an antipodean friend in slough was much appreciated. Will put a grease nipple in and fill the tube up with hot grease & let it set in the lowest point. Good idea? Or not?? Opinions please!
Anyway, I didn't get it all painted and back together for monday, so pushed he skorp back into service. Ran like a dog, "hunting", lots of complaints from the pipe with the occaisional really sharp <CRACK>.
But it was usable, and I hate the tube, so just got on with it trieing not to run to a halt on a fully closed throttle.
Redex and new petrol- a little better
Made sure the plug was fully home (got about 1 complete turn)- better still
Last night checked the jets. No obvious blockages and the float bowl was reasonably clean. Much cleaner than the SRX with its rusty steel tank. Hmmmm.. Maybe a little sweeter, but still the odd very loud bang. Going by Kings Cross, a wee wifey genuinely nearly dropped her shopping and gave me some verbal at the lights!! I apologised profusely! (someone was shot there on saturday night!!!)
Right, its gotta be the exhaust tappets closing up! After all I've never checked them since I got the bike, so thats about 3,000 miles. And maybe cadwell was just hard enough on it to cause them to just not quite be clear?? Up early this morning, whipped off the covers (and the radiator- bloody water cooling!!!) but they were spot on 6 thou. Arrrgh!!
Late already (and not making up any time now in front of my computer...!) I got the silicone sealant and went over all the very small leaks in the pipe- the headers are fine, but the can has been ground out a bit, and where its bolted together there IS the potential for small leaks especially if its moved a bit. Clear bath sealant judiciously applied round the bolts & washers- great stuff.
SO????
The <<CRACK-CRACK>> is no more! Ok, it still "ruffles" a bit on a closed throttle, but its much better. I shall check where my bodged-up link pipe clamps over (there are *tiny* wee leaks there) and get the old bath sealant out when I get back, see if it makes a difference... The fight goes on!!
I was surprised tho- the exhaust doesn't blow terribly but obviously its enough. Compounded with other things- old fuel, maybe a bit of varnish in the carbs, a slightly recessed plug maybe this is my problem?
Moral of the tale: "Preservation through operation"
(not masturbation, as I often like to think)
;-)
Cheers
a
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I'm going to use this post partly as a blog, partly as a notebook so I know what I've done! Hope this is ok, no need to keep reading/ replying if its not your bag!! Tho any insight to any of my drivel is obviously appreciated. Its bugging me, the bike handles *BRILLIANTLY* with the new rubber, fork springs, rebuilt shock linkage etc. but the fuelling (or it feels like it) is beginning to detract from my cornering joy...
Still popping occaisionally, but fairly certain exhaust is not the main problem.
Still "hunting" / hesitating about 4k, just when it want to pick up.
Not fuel, not dirty carbs, not plug, not knackered inlet rubbers, not closed up exhaust tappets, not sticky choke.
Possibly its electrical then:
feed to the coil?
Plug cap?
bad earth strap?
coil breaking down?
CDI?
Kill switch??? They're cheap n nasty!
Fuel pump?? Going lean would cause the hunting and banging, no? Vacuum inlet to the fuel pump?
Will check these and list findings.
a
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Aye Andy,
You old blogger!!!! ;-)
Just the obvious I suppose, "hesitate at 4K".
If you shut off a twitch, does she pick up and accelerate and then you are able to feed more petrol or does she just drop off?
Suggest the needle and weaken one notch if the former or the reverse if the latter. I still think 'AMAL' so you'll have to interpret if its one of these CV things!
Cheers, Bill
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Cheers Bill, but I'm not going to touch the carb settings. Its been dynojetted, but it was running very cleanly before, none if this problem. And the carb settings haven't changed, so I'm going to look for something that has.
Thanks for the ideas tho. Maybe it was the gremlin... After all the skorp is parked next to the racer in the garage. So a gremlin could have jumped off the srx to the skorp...!
:-)
Will invesigate electrics next, then fuel pump...
a
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Aye Andy,
Wee beasties eh!
I'd go fuel, rather than electrics just yet. Crap in pipes either side of pump, crap in tank tap, ridge on float needle or seat?
Whilst we're on this, any chance of some Ohms resistance readings from an SRX600 rectifier known to be working?
Resistance value between the two input spades for the white wires from the alternator?
Resistance value between the red feed to battery + pos. and the black to earth - neg. output spades?
Any resistance value between either input spade and the black or red outs?
Sally is boiling batteries and the alternator output resistance is 0.6ohms as spec. and charging at 5Krpm is 14v as spec. Can only be rectifier left and no values given by Yamaha. Just by another one, Sir!
'Cause we're off tomorrow will have to await return afore posting values from my 'suspect' instrument.
Thanks if you can help or post as start of a new thread if you prefer.
Cheers, Bill
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Hi Bill, will post srx values at/after weekend.
A couple of days ago on the way home, I pulled off the lights (sharpish) dropped it into a corner. As I opened the throttle to lift it out, it (heart stoppingly!) stuttered, before picking up again.
Oh ya bas****! Didn't like that...!
Then, last night, at the same corner it did it again
Oh ya bas**** again!
I immediately thought "float bowl sticking". Or similar. Problem exaggerated by the lean, open throttle sooks all the juice out the carb, and it goes a bit lean?
Will get the carbs off again and have a wee keek! While I'm in there, I'll check fuel pump (sure its fine), and any obvious electrics.
Cheers
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Slide sticking in the CV carb ? or diaphragm problems ?
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Cheers, will take the top off and have a look at the rubber.
The jet was clear...!
a
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Hi Andy, If the gremlin has jumped on to the skorp, I'd move the srx/racer out quick & store it elswhere!!!!!
I'd borrow a known working cdi & test how it runs before doing anything else!, remember, I have a ton of srx stuff here if you need to borrow anything?
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Burn It !
You wont have to worry then ! ;-)
Jethro
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Ha!! Yeah, the thought had crossed my mind!
Didn't get anything done (bar the addition of some redex to the tank). So its "as is".
did get the garage wired tho, so can now work on out of daylight hours. And the with a workbench, the garage is beginning to be quite usable. Am running an inverter from the van battery for the mo. I'll see how long it last, plus it means i don't have to shell out for a genny just yet!
a
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Found the problem....!
Wanna know what it was?! Don't I feel daft now??!
Or maybe I'll tease you and make you wait for the newsletter....
Anyway, the skorp is now a deliciously free-revving (to the limiter) bag of fun, with big sooky carbs and a rorty pipe, and super-sticky new tyres which make it go round corners too!
And the looks of "Whats one of them?" from the shiny-shiny crew at the lights is fun
a
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Well done matey. I'm guessing it's something like poor cable fitment or breather pipe missing?? Am I close???
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Hey Pat-
Not quite. Similarly elementary tho. Wasn't fuel after all, and I must confess its something I NEVER check...
Any other ideas??
a
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Kill Switch ?
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Nope!
1 more guess, and I'll tell you...
(i am a sad loser)
a
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Hey Pat-
Not quite. Similarly elementary tho. Wasn't fuel after all, and I must confess its something I NEVER check...
Any other ideas??
a
Hmmm, not fuel, then definiatly electrical. Something checkable as opposed to breakable and easily fixed rather than replaced. Created a flat spot at a particular rev range/frequency or was it angle of lean??. A puzzle for sure.
HT lead to plug cap?? coil earth?? battery sliding about/poor connections?? Have I got it??? If not I give up :-)
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Not fuel, you tease! I was going to suggest tank cap breather obstructed by tank bag or crimping breather with pressure from leg on tank!
Not the silk scarf over the intakes!
How about the screw on 'bulbous bit' which threads onto the end of the spark plug being loose. Or your seat displacing the battery when shifting your weight for the corner. Finally, the edge of the tank shorting out the loom where it passes between the tank and the seat on the right hand side at the rear of the tank.
Having written this I realise I'm still thinking SRX and not Skorp so it is probably all B's!;-0
Festival of Speed calls! STOP tweaking my suspenders and tell us all!
Cheers, Bill
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Clogged air filter
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Loose spark plug!!!
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Righty Ho!
All very good guesses but not quite there.
I checked the carbs, inlets etc for a 2nd time.
Didn't touch the jets but checked the float and valve were good. And the CV rubber was sealing (bitch to get back on its wee seat!). And the breathing tube was clear. And the cables were good.
was the choke sticking on? Pretty sure it was fine, but thought I'd check the plug anyway.
****After all first thing I did after the lay up was put a new plug in...*****
The plug had been kept in my old garage. Which was a van.
When I whipped the plug out, the colour was very encouraging. But the gap wasn't!! It was tiny. 9 thou to be precise. Set it to the standard 35 thou, and all was well with the world.
I then looked at my dismanteld carbs on the bench and felt very stupid.
Morals of the tale:
1) It IS the simple things you have to check first.
2) Vans aren't good garages. Sometimes they're not very good vans.
3) Just because the part's been replaced new doesn't mean its fail-safe.
4) Lack of use kills (modern) motorbikes
5) I have still never had a case of bad petrol, or petrol blocking the jets!
Cheers all for your help. Much appreciated!
a
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Afternoon Andy,
Don't drop your plugs on the floor! Thank goodness, I can remove the suspenders, they were killing me!
Cheers, Bill
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Righty Ho!
5) I have still never had a case of bad petrol, or petrol blocking the jets!
Well you are very lucky ! So Far !!!!!!!
Pulled a carb apart today off a XR250,been stood for quite awhile.
Only 36Kms on the clock.
What a rank,racid mess and smell !!!!
A thick green coating everywhere,pilot jet solid crap and had to use(GENTLEY !)a wire brush on the main jet associated needle jet.
Jethro
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Resurfaced the drive from the crap from an Amal I bought...