I get snatch..........

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devlin
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I get snatch..........

Post by devlin » Mon Apr 09, 2007 1:09 pm

............... :shock: .............ahem............when doing slow speed manouvres and when I roll the throttle open from full closed. Seems to be very fine line between no reaction and too much throttle. If I really concentrate on it I can effect a smooth transition but it stops me concentrating on the rest of what I am doing. Is this an inherent character trait of the bike or the carbies? What can I adjust to take some of the hesitancy away? Thanks.
"Racing is life, everything else is just waiting" - Steve McQueen
Four wheels move the body, two wheels move the soul.

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Post by cheesie » Mon Apr 09, 2007 2:47 pm

does that on mine, even more so since I re jetted, might leave it into tuning shop see if he can iron it out, though its not that bad, only while doing sub 30 mph speeds around town is it anoying I thought its maybe just a tiwn thing

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Re: I get snatch..........

Post by Killerwhale » Mon Apr 09, 2007 4:46 pm

t-rex 850 wrote:............... :shock: .............ahem............when doing slow speed manouvres and when I roll the throttle open from full closed. Seems to be very fine line between no reaction and too much throttle. If I really concentrate on it I can effect a smooth transition but it stops me concentrating on the rest of what I am doing. Is this an inherent character trait of the bike or the carbies? What can I adjust to take some of the hesitancy away? Thanks.
http://www.kedo.com
They have a "anti rückel kit" that cures this ok....
Lower gearing and adjusting the throttle cable to no slack is standard things to do also.....
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phuk72
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Post by phuk72 » Mon Apr 09, 2007 4:54 pm

TRX is very sensitive to chain adjustments, slack in throttle cable and being properly jetted.

Mine doesn't snatch at all but, generally speaking, it is a trait of most twins.
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Post by trixynut » Mon Apr 09, 2007 7:35 pm

...agree with Phuk: make sure the throttle cable has NO SLACK at all and it will cure the snatch :shock:

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Max
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Post by Max » Tue Apr 10, 2007 12:16 am

Yes, a good tight grip will make the snatch much better.
Max

(TaZ, tz250w)

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devlin
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Post by devlin » Tue Apr 10, 2007 12:29 am

Thanks guys. I don't mind a bit of snatch in the right time and place though.
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Re: I get snatch..........

Post by dfh » Tue Apr 10, 2007 12:59 am

t-rex 850 wrote:............... :shock: .............ahem............when doing slow speed manouvres and when I roll the throttle open from full closed. Seems to be very fine line between no reaction and too much throttle. If I really concentrate on it I can effect a smooth transition but it stops me concentrating on the rest of what I am doing. Is this an inherent character trait of the bike or the carbies? What can I adjust to take some of the hesitancy away? Thanks.
CV carbies, like farting in bed, are inherently anti-snatch.

All the replies were on the money but other things to consider are carb balance, vacume leaks around the carb rubbers or in the thousand of vacume pipes runnung to the fuel pump and stuff, throttle position sensor alignment and valve clearances. TRX's are snatchy at low revs by nature and a bit of back brake and clutch slip helps.

FWIW I was playing roll ons with my mates on a recent trip away and the BMW and Aprilia, both fuel injected twins, would instantly jump a bike length or so as soon as the throttles were whacked open from a constant speed . The only other bike on CV carbs, a SV650, would show the same softer response as my TRX.

For straight line drag races CV carbs suck ( ... ooh an engineering joke) compared to fuel injection but not as badly as the pumper Dell'orto carbs on my Guzzi. But when railing through a sweeper on the footpeg or driving out of a tight, damp snat... no no corner I mean to say.. :oops: then give me CV carbs over fuel injection anytime.

DFH
Now with 140,000 on the clocks, X-mas tree didn't kill it & I still love it.

Sarg

Re: I get snatch..........

Post by Sarg » Tue Apr 10, 2007 10:04 am

dfh wrote:[quote="t-rex
But when railing through a sweeper on the footpeg or driving out of a tight, damp snat... no no corner I mean to say.. :oops: then give me CV carbs over fuel injection anytime.

DFH
I'll second that. On the FJR when on the limit the application of throttle needs to be with care, especially when the engine revs are not extreme. say 4 to 7 thou. It really comes on with a boot. I have had many riders say the same about many injection systems. / bike with.

Sarg

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Post by Wombat » Tue Apr 10, 2007 12:06 pm

"For straight line drag races CV carbs suck ( ... ooh an engineering joke) compared to fuel injection but not as badly as the pumper Dell'orto carbs on my Guzzi."


Ain't that the truth, re Dell'ortos. The ones on my Guzzi were so bad and worn out that I went to the extreme and fitted FCR41s

Bob
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Post by dfh » Tue Apr 10, 2007 12:31 pm

Now then Mr Bob the Wombat... Am I alone in the belief that the TRX channels the spirit of Guzzi more than Ducati, or do I stand alone on that one?

DFH
Now with 140,000 on the clocks, X-mas tree didn't kill it & I still love it.

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devlin
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Re: I get snatch..........

Post by devlin » Tue Apr 10, 2007 2:47 pm

dfh wrote:All the replies were on the money but other things to consider are carb balance, vacume leaks around the carb rubbers or in the thousand of vacume pipes runnung to the fuel pump and stuff, throttle position sensor alignment and valve clearances. TRX's are snatchy at low revs by nature and a bit of back brake and clutch slip helps.

DFH
I checked the throttle cable and it is perfect. Off the throttle stop I get instant movement at the carb. I will check that the carb rubbers are seated properly and that the hoses I undid the other day are put back where they are meant to be. It seems like maybe a carb balance or jetting (repacked stock cans) or maybe the TPS needs a tweak. Just seems to be a very fine balance between not enough throttle and too much. Good fun trying to figure it out anyway. Thanks again for the info.
"Racing is life, everything else is just waiting" - Steve McQueen
Four wheels move the body, two wheels move the soul.

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