Can’t get it running 😔

  • Larsson
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Can’t get it running 😔

12 Mar 2025 12:18
#909995
Hi there!

I have this KZ750e -81 that I’m close to giving up on.
I bought it in pretty bad shape, barely running.

I have done the following, although it was some time since I did some work on the bike.

- honed the cylinders (they were in spec)
- new pistongrings
-lapped the valves and adjusted them into spec
- new gaskets head and cylinder
- cleaned and renovated the carbs. Cv34’s
- new ignition coils 3ohm Dynatek (the bike has Dyna S)

The timing is on spot and the compression were not the best but at least pretty equal.

Since the original airbox were shot I put on pods together with 4 into 1 exhaust on and rejetted with jets from 6sigmajetkits.

Before rejetting I tried to start it and it started well but ran very poorly on higher revs, of I remember correctly.

The problems today

1.
After rejetting it starts well but climbs up in revs fast without me touching the throttle. 
After starting I have to cut the engine off within seconds.

2.
It does not fire on all cylinders anylonger for some reason.

I really want to get this bike back on the road, but now I don’t know what to test or do anymore.
I’m about to give up, but that would be to admit defeat.

Please help me out on this and I will keep you updated on the progress!
Let us get this thing running as it should!

Kind regards
Kristian Larsson from Sweden
 

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  • Wookie58
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Re: Can’t get it running 😔

12 Mar 2025 12:36
#909998
Have you replaced the carb to head rubber manifolds (if they haven't been changed there is a good change they have hardened and are causing air leaks)

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  • Larsson
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Re: Can’t get it running 😔

12 Mar 2025 12:43
#910000
Hi!
Missed to mention that but yes, they have been replaced.

But maybe they haven’t seated correctly? Although I doubt it. But definitly a thing to check.

But thank you for your input!

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  • Wookie58
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Re: Can’t get it running 😔

12 Mar 2025 12:56
#910003
Are the vac ports capped on the carbs (except the vac pipe to the fuel tap)

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  • Larsson
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Re: Can’t get it running 😔

12 Mar 2025 13:14
#910006
Yes, they are.

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Re: Can’t get it running 😔

12 Mar 2025 13:45
#910009
What make of pods are you using ?
Have you done a thumb test to check the diaphrams ?
Have you tried re-fitting the stock jetting ?
Climbing revs would normally indicate an air leak or mechanical issue with the throttle linkage

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  • Larsson
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Re: Can’t get it running 😔

12 Mar 2025 14:37
#910013
I don’t remember the brand of the brand of the pods but they are high quality.

Hopefylly I’ll get some time in the garage this weekend and I’ll test those things 👍

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  • hardrockminer
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Re: Can’t get it running 😔

Yesterday 14:40
#910035
Which cylinders are firing?  
I have several restored bikes along with a 2006 Goldwing with a sidecar. My wife has a 2019 Suzuki DR 650 for on and off road.

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  • Nessism
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Re: Can’t get it running 😔

Today 19:10
#910046
Sounds like carb problems.  I suggest  you source a stock airbox.

When cleaning the carbs, did you ungang them? Soak in carb dip after removing all hard parts?  Replace all the various O-rings.

The bleed pipes and pilot jets must be removed and held up to a light, to make sure the tiny hole is open.  And the pilot circuit must be clean.

 

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