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1Back to top Go down    Throttle body #4 won't balance on Thu Sep 01, 2016 9:14 pm

Roland5

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I'm attempting to balance the TBs on my 85K100RT with a CarbSync and my number 4 cylinder won't adjust up or down. The adjustment screw moves and works in and out but no adjustments are made in the level of the fluid (vacuum). I'm wondering if I've got it hooked up wrong. I'm removing the vacuum caps from cylinders one through three, and then removing the vacuum hose which comes from the fuel pressure regulator. to the number four vacuum port. I hook the sync to the four TBs and leave the hose from the fuel pressure regulator unattached. All other adjusters/adjustments work. I even switched the sync hoses for three and four and found the same results, no adjusting number four when the screw was adjusted. Haven't replaced the orings on the adjustment screws.

thanks for the assistance.
Roland


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Roland Antumblen
85K100RT - BlacK Beem
Toad Suck, AR
    

2Back to top Go down    Re: Throttle body #4 won't balance on Thu Sep 01, 2016 10:55 pm

charlie99

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probably the bypass screws- jets are ok ... but wouldnt hurt to clean them out with a blast of carbi cleaner ...I have seen the inlet side vent tube blocked before with carbon and crap ..

you have made sure that the tappet clearances are good and not too tight ? always do that before attempting a tune .

after the clean ....there is a possibility that the linkage is holding the butterfly slightly open

the bypass venturi is a difference type vacuume setting(either side of the butterfly ) rather than absolute

hope that helps a little ...or what makes sense to me at least


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cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

3Back to top Go down    Re: Throttle body #4 won't balance on Thu Sep 01, 2016 11:45 pm

Holister

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All good possibilities charlie particularly the butterfly. To add to that scenario, the #4 TB linkage adjusting screw may have been tampered with. Its the only one accessible without removing fairing and may have been adjusted mistakenly by a PO thinking it was an idle adjustment. That screw should have some paint on it (applied in the factory) so that it's evident when it's been tampered with. If that's the case it will be difficult to get it back to factory setting. You'll need to remove the plenum.

Another possibility is that you have a bad air leak below the TB such as in the lower rubber or your #4 injector is not seated properly. O-ring may be perished.

Cheers


__________________________________________________
1988 K100RT VIN No. 0094680
1989 K100RT VIN No. 0097367 (naked)
1996 K1100RS VIN No. 0451808
Fuel: 95 Octane
Engine Oil:Nulon Full Synthetic 15W50
Gear Box Oil: Nulon Synthetic 75W90
    

4Back to top Go down    Re: Throttle body #4 won't balance on Fri Sep 02, 2016 12:05 am

duck

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I'd guess leaky boot between the TB and cylinder head.


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Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

5Back to top Go down    Re: Throttle body #4 won't balance on Fri Sep 02, 2016 1:21 am

charlie99

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all good suggestions


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cheezy grin whilst riding, kinda bloke ....oh the joy !!!! ...... ( brick aviator )

'86 K100 RT..#0090401 ..."Gerty" ( Gertrude Von Clickandshift ) --------O%O
    

6Back to top Go down    Re: Throttle body #4 won't balance on Fri Sep 02, 2016 3:11 am

ungaas

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Do you have a T piece connector between no 4 tb, vacuum tube and gauge setup.


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88 K100 Unfaired 0033026

92 K1100RT 6455097
    

7Back to top Go down    Re: Throttle body #4 won't balance on Fri Sep 02, 2016 12:20 pm

brickrider2

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I thought the "best practice" was to plug the end of the tube running to the fuel pressure regulator. No?

    

8Back to top Go down    Re: Throttle body #4 won't balance on Sat Sep 03, 2016 6:56 am

duck

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JMHO but what I do with my Carbtune is have a T to the FPR on the #4 hose since that's closest to what happens when riding.


__________________________________________________
Current stable:
86 Custom K100 (standard fairing, K75 Belly pan, Ceramic chromed engine covers, paralever)
K75 Frankenbrick (Paralever, K11 front end, hybrid ABS, K1100RS fairing, radial tires)
86 K75C Turbo w/ paralever
94 K1100RS
93 K1100LT (x2)
91 K1
93 K75S (K11 front end)
91 K75S
14 Yamaha WR250R
http://www.ClassicKBikes.com
    

9Back to top Go down    Re: Throttle body #4 won't balance on Sun Sep 04, 2016 11:53 am

Point-Seven-five

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+1. I'm with the Duck on staying close to actual running conditions.


__________________________________________________
Present:
1994 K75RT
1994 K75S
1992 K100RS

Past:
1982 Honda FT500
1979 Honda XR185
1977 Honda XL125
1974 Honda XL125
1972 OSSA Pioneer 250
1968 Kawasaki 175
    

10Back to top Go down    Re: Throttle body #4 won't balance on Sun Sep 04, 2016 12:27 pm

brickrider2

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I rechecked and tweeked the balance on the K110RS TBs using the T-connector on #4 as suggested and the bike now has never run better. Sweet! cheers

    

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