Lumpy as me mums gravy :(

First topic message reminder :

Hi all, had my cat since I passed in June this year. Only problem is it runs rough and lumpy at slow speeds. Normally under 3k when there is just a whiff of throttle. The bike will judder and generally run rough,until I open the throttle more and then it's fine. Makes it a bit of a pain round town or in traffic Was led to believe that this was the way the cat is but since discovered it's not :( the bike is long over due for a service as I took the air-filter off earlier this week and found half a forest including wildlife in the filter. Cleaned it out and it runs better but not perfect problem is still there. Planning on doing a service chaining the plugs, oil, filters, and cleaning and balancing the carbs. However read that it could be the tps? But not sure what this is. Wondering weather anyone else has had this problem and if a good bit of tlc will cure it? Or to look for something specific. Oh and already been suggested that I should ride faster then it won't be a problem.ha ha looking forward to your input folks.

Littledel wrote:Well quick update for you all.
Done a fair bit on the bike. New plugs, air filter, oil & filter, fuel filter. And my first attempt at balancing the carbs. Which brings me on to my next point. I have the carb tune tube type ones and the tube attached to the no 4 carb didn't flutter like rest it went up and down when I adjusted it but just sat there when I left it. Any one no what this could b? Have a feeling there is a blocked jet on that carb, could cause this?(didn't take em off and clean em) :( lazy I know. Anaways. Feel a few numpty points would suit me here.
1st forgot to turn the fuel on at the tank when instated
2nd forgot to turn the fuell off when finished.
3rd took the bike out for a test ride ran terrible thought I had messed summet up. Came home looked down when putting the prop stand down, only to find...........a vacuum hose plug :S whoops fitted it went back out on it a lot better but still not right. Going to have to take the carbs off and clean em and balance em again, will spend a bit more time on em.

Nah, dont think a numpty point is needed there mate.
Good on you for trying to sort it yourself Nothing like a good bit of tinkering.
Not sure about the reading your getting on the carbs, didnt do mine myself so I cant comment.

Just remember, its a learning curve. We have all been there, hopefully someone can answer your carb question.

Sean.

Ha ha cheers Sean for a first attempt didn't think
I did to bad.lol have to remember it all for next time. In
Some ways wish I had of paid someone else to balance the carbs. But then again have 4 bikes in the yard all with carbs so thought i would give it a try £65 for the gauges and £5 for for a bit of hose and jubilee clips soon pay for themselves. Did notice a crack
In the rubber from the carb to the block as well have a strong feeling this could be a culprit for the problems either that or a blocked jet.

yeah, that sounds like the split rubber could be causing the erratic reading.
Sort the rubber, but if your thinking of cleaning the carbs I would do that first, then obviously balance them after.

Very rewarding job!!!

Aye but the cracked rubber was on no3 cylinder this was on the 4th gauge :/ will want doing tho should have cleaned the carbs in the first place bit took a short cut and didn't really pay off. Have to wait and c this weekend. Bit ya right sean something about doing things ya self, like wetting yourself in a dark suit.......ya get a warm feeling inside bit no one else notices.ha ha. Never mind running bet that it was just not perfect.

The gauges are quite often erratic at low revs mate, they recommend turning the tickover screw up A little when balancing. Personally I always balanced mine at the revs I rode at most often which was about 4k iirc? This ensures for the smoothest of rides, worked a treat too.
Worth trying number 4 gauge on a different cylinder too just incase its a faulty gauge?

Cheers Rob might try Putting it on another on c what happens. just funny how all of them were bouncing a little but the 4th on was still until I adjusted the screw to balance them.and it either went up or down. I did move the tickover to about 2k might try it at about 4 tho see how it works.

Sorry to hear she's not running right. Didn't have a problem when i traded it in. A few pops and gurgles on the overrun which i put down to the carbs needing balancing, but other than that it was running well. Kept ontop of the oil changes, and new filter each time so you shouldn't have any probs there. Will prob need the valve clearances checking soon. Changed the pads not too long before she went. Tyres were quite new too. Put corsa's on and it felt loads better than the battlaxe 021's i had on before. She chewed through the front tyre just as fast as the back on the 21's, so wouldn't advise putting a set of those on when the time comes for a change. Also changed the chain and sprockets about a year back.

Cheers

Back to the lumpy stuff - if it's the pilot jets partly blocked, try some IPA (isopropyl alcohol - not the stuff you brew in Burton) ot Silkolene FST in the petrol. Or just give it a few fills of Shell V-Power or similar.