KZ750 Twin Won't Start, STILL wont start!! Updated

steell wrote: I hesitate to step in because Motor Head is doing excellent, but I figured you need to know that the four brush kit will make the starter turn backward.

Went through all that on a 440 twin on the twins site.

That is good info Steel. That must be as the engine on the twin runs backwards, the starter rotation is also reversed. So the 4 brush assy fit the housing though, and was made to work other than rotation? was changing the Poles tried, as this should change the direction back.

gengomerpyle wrote: well he did say his battery was shot. so i would think he should buy a new battery and get it fully charged. seems like hes running in circles right now.

When i take the perfectly good & fully charged battery out of my race bike & try it it makes no difference.

I'm using a "Snap On" jump start pack on the bike at the minute. There is no issue with it putting out enough power, it's capable of easily starting 3Litre & 5Litre diesel engines with dead batteries.

Forgive me if I missed something, but have you ever started the bike using the kickstarter so you at least know it runs?

650ed wrote: Forgive me if I missed something, but have you ever started the bike using the kickstarter so you at least know it runs?

I've had the bike about 2 months now & im just working on it bit by bit.

750steve wrote: When i viewed the bike at the time of purchase the bike was jump started off a car, the starter whined a bit (obviously the planetary gear) but eventually started.

As said, the bike was going when i bought it though there are a few issues. The starter button doesn't work, the battery is totally dead & the worst thing is someone has tried to wire in a reg/rect that cant work with the bike as its for the later type charging system. That would explain the dead & done battery.

i don't know if you need anymore help, but I'll post this cable checking info to add to what I posted earlier.
Voltage drop, on the cable will show resistance bad cable. If say the battery measures 13v at the positive terminal, then drops to 11.5 when craning, then check the other ends of the Positive cable. One going to the solenoid, and then at the starter post. It should still measure the 11.5v, or real close like 11.3v if cabling is good. Now the same for the Negative cable.

Im going to remove the starter tonight & bring it into our car workshop tomorrow. A Tech is going to resolder the connections to the + post inside. I'll bring the + wire from the battery including the solenoid in too & he will check the voltage drop.

After that im throwing the starter off a high bridge..............& seeing if i can catch it on the way down!

750steve wrote: Im going to remove the starter tonight & bring it into our car workshop tomorrow. A Tech is going to resolder the connections to the + post inside. I'll bring the + wire from the battery including the solenoid in too & he will check the voltage drop.

After that im throwing the starter off a high bridge..............& seeing if i can catch it on the way down!

Sorry it is such a pain to get it right.
If you take in the Positive cables, also take the negative. It takes both for a complete circuit, if one is bad, well it won't get the current it needs to apply the torque.

You'll get it figured out and the bike will start right up. Then you can fix the charging and other issues.

Well im in a much happier place tonight even though it is 3am!

I took the starter motor apart again & re-soldered the connections, tested the motor & put all back together. I hooked the jump pack up th the battery & jumped the solenoid, hey presto the motor turned over! YES!!!

The bike still didn't start but im sure some minor adjustments & it will, i did hear it going before i bought it remember. These things must suck up some juice, it ran the battery pack down to about 50% charge & then it wouldnt turn the motor over but im calling it a successful night anyway.

I'll try to get it running tomorrow night & hopefully when i do i can start to strip the bike for its rebuild on friday when im off work.

I cant tell you guys how happy i am, i feel very silly for nearly giving up last night & thank you all very much for your sound advice. Hopefully i can return the helping hand to some other people some day.

No doubt when i eventually get my pod filters on (prob in about a year at this rate of going!) & the carbs cleaned etc i'll need some guidance on jets & the like to get it running properly.

I have learned a valuable lesson; sometimes its better to walk away & have a think than to beat yourself up about a situation!

Do a search on Pods before buying them, and then decide.
I'm pretty sure the guys here won't give up, if you don't.
Start another thread for the next gremlin to banish. :whistle:

Oh dear, the pod comment sounds good! lol

Thing is i kinda need to as im building a cafe racer from this bike & i would like that central area where the battery & electrics are to be 'see through' as much as possible.

I've already got some good advice & a wiring diagram from Loudhvx when it comes to rewiring the whole bike so the electrics are to be hidden as much as possible as well.

Small battery advice needed soon though, was going for a Shorai but i've been told to be cautious about them, i'll need WAY smaller than OE anyway!

Thanks Motor Head, you've been a star!

Quick search & i see what you mean! haha

650ed wrote:

otakar wrote: You don't want KZ750 carbs because they are Keihin and they are SHIT.

:laugh: :laugh: :laugh: No argument here.

Motorcycle Batteries
www.ballisticparts.com/products/batteries/12cell.html
www.shoraipower.com/
www.motydesign.com/8cell_prod.php
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