high rev at start

  • mnrenfro
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high rev at start

02 Apr 2018 19:09
#781183
My 76 KZ400D exhibits a problem where it revs way too high when it first starts. The throttle cable isn't stuck, so I'm not sure why it does this. Any help is appreciated.

Marshall

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  • Nessism
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Re: high rev at start

02 Apr 2018 22:16
#781191
Sounds like a lean condition caused by a vacuum leaks.
Ed
Carb O-ring Kits : www.kzrider.com/forum/14-vendor-forum/62...rburetor-o-ring-kits

www.kzrider.com/forum/faq-wiki/618026-new-owner-things-to-know

1981 KZ750E2
www.kzrider.com/forum/11-projects/604901...z750e-project-thread
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  • zed1015
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Re: high rev at start

03 Apr 2018 04:33
#781194
Are you sure it's not just when it's on choke.
If so, that is normal.
Otherwise as stated it could be air leaks at the inlet manifold, Sticking choke plunger etc.
AIR CORRECTOR JETS FOR VM CARBS AND ETHANOL RESISTANT VITON CHOKE PLUNGER SEAL REPLACMENT FOR ALL CLASSIC AND MODERN MOTORCYCLE CARBURETTORS
www.kzrider.com/forum/23-for-sale/611992...lide-mikunis?start=1






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Re: high rev at start

03 Apr 2018 06:29
#781199
Thanks. It's not the choke plungers, but it could be leaks at the intake manifold. Not sure how to test for a leak there, but I can at least check and make sure the screws are tight.

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  • ajsfirehawk
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Re: high rev at start

03 Apr 2018 09:07
#781214
After the startup and the engine settles down, shoot a couple quick bursts of starter fluid across the intakes. If if revs up, there is a leak.
80 KZ1000 Z1 Classic
83 KZ1100 LTD
18 Z900RS
23 Mach 1
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  • Patton
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Re: high rev at start

03 Apr 2018 09:53 - 03 Apr 2018 09:54
#781215
Assure advancer isn't sticking.
Good Fortune! :)
1973 Z1
KZ900 LTD
Last edit: 03 Apr 2018 09:54 by Patton.
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Re: high rev at start

03 Apr 2018 11:27
#781221
recheck throttle cable return spring.
cable may be sticky, needing lube.
'83 KZ750 Spectre, '01 ZRX1200R, '03 ZZR1200, '84 GPZ900R, 7 Hondas, 1 Yamaha
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