Running diagnoses please

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Drunkn Munky
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Running diagnoses please

Post by Drunkn Munky » Fri Mar 11, 2011 10:42 am

Right i have the 30 motor in the 35 frame now, 35 starter clutch and pickups fitted, ignitech CDI. Vacume is working and fuel is flowing, all 4 plugs are sparking.
Using 35 carbs with stock settings and 110 jets all round, k&n filter and stock intake system. Bike wont start with the usuall full choke and no throttle approach and needs throttle to start and keep it running.
Theres also a bit of popping and back firing which is leading me to think its plugs, there not new but removed from a running bike, any ideas before i go and get raped by the honda dealer for plugs?

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ibby4585
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Re: Running diagnoses please

Post by ibby4585 » Fri Mar 11, 2011 10:49 am

That's got to be carb related mate. What are mixture screws set at?

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Drunkn Munky
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Re: Running diagnoses please

Post by Drunkn Munky » Fri Mar 11, 2011 10:57 am

1 and 5/8th i think, what ever stock is. i never tested these carbs on the other engine so dont know 100% they run. Everything else is checking out so i'll rejet the 30 carbs and try them, what jets are you running on the OKI with the TSR's?

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ibby4585
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Re: Running diagnoses please

Post by ibby4585 » Fri Mar 11, 2011 11:06 am

124's all round but with RO needles it's pretty nice all the way through the rev range. Mixture 2 1/4 out. Ive got some spare 30 carbs good for spares if you need them.

Kris

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CRM
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Re: Running diagnoses please

Post by CRM » Fri Mar 11, 2011 11:17 am

I learnt a big lesson over the years - and that float height is critical.
not to the extent of any flooding or starting, but more how it affects flat spots.
i have had a bike with a huge 6k hole, only to have an extra 1mm of float to give is a real kick up top and no more flatspot. no other jetting or dodgy slide drilling required.
if the carbs are known as good then new plugs is the way forward too. always good to have a spare set.
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Drunkn Munky
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Re: Running diagnoses please

Post by Drunkn Munky » Fri Mar 11, 2011 4:22 pm

Well 35 carbs were leaking slightly from the front right, couldnt be arsed to investigate so put some 122's in the 30 carbs with the RO needles and put them in and found out 30 carbs go into 35 rubbers a treat even tho the 30 carbs are bigger :?
She popped and banged for a bit but smoothed out and warmed up nicely, also put a new set of plugs in that i found in the draw :grin:

So lads it looks like she's a runner, MOT next week Woohoo!

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royster81
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Re: Running diagnoses please

Post by royster81 » Fri Mar 11, 2011 6:28 pm

Good good but she better look fuckin gorgeous....
It's not having what you want but wanting what you've got....Loud ,Proud and Modified ....

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Drunkn Munky
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Re: Running diagnoses please

Post by Drunkn Munky » Fri Mar 11, 2011 6:37 pm

royster81 wrote:Good good but she better look fuckin gorgeous....
errr no
Image
Just need some slim indicators for the rear then she's going for the MOT as she is, multi coloured panels and loud pipes :grin:

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skinnydog0_0
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Re: Running diagnoses please

Post by skinnydog0_0 » Fri Mar 11, 2011 8:29 pm

Drunkn Munky wrote:
royster81 wrote:Good good but she better look fuckin gorgeous....
errr no
Image
Just need some slim indicators for the rear then she's going for the MOT as she is, multi coloured panels and loud pipes :grin:
Hey Tony,
If you ever go mad and want to sell those exhausts, let me know :mrgreen:

I found that standard pilot screw settings on the 35 carbs are slightly rich, not too bad but it would need setting on the dyno to get it spot on.
But like CRM said, worth checking float heights.
Get some pics up of her when she is fully back together :peace:
An NC is for life, not just for Christmas!

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micpec
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Re: Running diagnoses please

Post by micpec » Fri Mar 11, 2011 10:58 pm

Tony, I had similar issue at the initial start with the TSR system on the mint NC35. It suffered from the low back pressures in this set-up due the TSR race carbon end cans, that I admit were also worn out a bit. After balancing the carbs, fitted all new Iridium NGK plugs and set mixture 2 turns out, the starting procedure improved a significant. With the new Ti superpole cans I set mixture back to 1 5/8 turns. From that point any cold start goes smooth with only choke on as it should be from factory.

Good progress on the NC30 motor in the NC35 frame works...hope it goes well with MOT (although the TSR cans are loud...!.. :whistle: )
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