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Jetting questions.....again....

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Old 04-18-2014 | 12:51 AM
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Jetting questions.....again....

My bike is stock (I presume) as nothing says otherwise. It goes well apart from 3 things.

It pops a lot from the pipes on deceleration. I have done the pair removal but today turned the read plate to make sure, have not ridden it since. So that may be solved.

But the big one is its not smooth down low and give a lean backfire through the carbs sometimes on throttle roll on.

It will only start with choke if the bikes been sitting. And a lot of it.

Now I have read the carb setup thread which says run 48 pilots and lift the needles. But James Daugherty says they only need the stock 45 pilots.

To me the backfire through the carb and the need for choke are lean pilot jet. Ive yet to adjust the pilot screws as I dont have the tool to get them out. I have a pair of the thumb adjustable ones on the way.

Bike is stock apart from RS3 yoshi's and pair removal. The bike came with a K&N filter in a bag but the previous owner says the bike wont run with it on.

So I think the 48s are needed along with shims. I will leave the mains at this stage but either get a long stack from the front carb or block a hole in the slide.

Now for track days should I set up a another set of carbs with short stacks?
Old 04-18-2014 | 02:29 AM
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Oh, just checked my jet box and found 3 x 0.5mm shims. Hope they are the right bore.

Might just chuck them in tomorrow. Should be able to do that without pulling the carbs out.
Old 04-18-2014 | 08:37 AM
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If you look at 8541Hawk's carb setup thread, many people benefit from 48 pilots and a good carb sync. The 45's in there make it run lean down low (and give pops on deceleration). Others find just the opposite, and replace 48's that are in there.

I'd give it a shot at least... it seems for emissions reasons Honda would tend to tune lean from the factory.
Old 04-18-2014 | 12:37 PM
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Originally Posted by 7moore7
If you look at 8541Hawk's carb setup thread, many people benefit from 48 pilots and a good carb sync. The 45's in there make it run lean down low (and give pops on deceleration). Others find just the opposite, and replace 48's that are in there.

I'd give it a shot at least... it seems for emissions reasons Honda would tend to tune lean from the factory.
Yes ive read that thread. To me I have all the symptoms of a lean condition. I will get the jets next week and am waiting on Jack Flash to send me some finger adjustable pilot screws. Today I will sync the carbs and lift the needles as I have the right shims. Probably to the TPS as well.
Old 04-18-2014 | 03:57 PM
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Well others can claim that they don't need or run well with 48 pilots.
All I can say is mine and the ones I have tuned seem to like them.

As a side note, I know the UK spec bikes came stock with 48s (can't say for sure about other countries) from around 2000 on, so take that for whatever it is worth.
Old 04-18-2014 | 11:52 PM
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Originally Posted by 8541Hawk
Well others can claim that they don't need or run well with 48 pilots.
All I can say is mine and the ones I have tuned seem to like them.

As a side note, I know the UK spec bikes came stock with 48s (can't say for sure about other countries) from around 2000 on, so take that for whatever it is worth.
Well Im taking it on how it runs ad rides. But I think your right.

Today I blocked a hole in the front slide and lifted the front .5mm and the back 1mm. Also fitted lines for the carb sync. Did the TPS set and it was reading 890 at the start and 500 once it was done. Found an uncapped vac line which is what the decel popping would have been.

I also dumped the throttle return line.

So mid to top end it goes way better. Much better power. No more carb coughs. But bottom end is out. At low speed and constant throttle its surging a little and its hunting at idle. I cant adjust the pilot screws as I dont have the tool. But I have some of the finger adjust screws coming from Jack Flash. I also have a pair of 48s coming. I may try the 45s with the scews but as the 48s will be here first I will try them first with the stock screw settings.

Found this in the carbs......
Attached Thumbnails Jetting questions.....again....-100_2131.jpg  
Old 04-19-2014 | 02:30 AM
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NZ my Storm has been tough to set up. I'm the 3rd owner but I have its full service history. It seems every tom dick and harry has had a go at the carbs since the 1000km service.
I have now tuned out most of the low throttle surge and idle hunt with a stonking top end. I'm running 48 pilots a K & N and CF Delkavics.

Im now convinced a Dynojet kit will "cure it" so I've ordered one.

This bike is almost doing my head in. Lucky I can walk away and jump on my Bandit.
Old 04-19-2014 | 03:13 AM
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Originally Posted by 2wheelsagain
NZ my Storm has been tough to set up. I'm the 3rd owner but I have its full service history. It seems every tom dick and harry has had a go at the carbs since the 1000km service.
I have now tuned out most of the low throttle surge and idle hunt with a stonking top end. I'm running 48 pilots a K & N and CF Delkavics.

Im now convinced a Dynojet kit will "cure it" so I've ordered one.

This bike is almost doing my head in. Lucky I can walk away and jump on my Bandit.
Your on NSWBandits? I used to be when I had my K1 1200.

Dump the K&N. Sounds like the cause of problems.
Old 09-02-2014 | 11:34 PM
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Update where Im at. After fitting alloy stacks I found she was very fat in jetting. To the point of blowing black smoke.

So now im at 1 1/4 and 1 1/2 turns on 48 fuel screws. Just 1 .5mm shim under the rear slide. 1 hole in each slide blocked. Stock mains.

Rides well with good power.

Seems the alloy stack have enriched my bike greatly.
Old 09-03-2014 | 12:06 PM
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What is your elevation ASL?
Old 09-03-2014 | 12:39 PM
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Originally Posted by 8541Hawk
Well others can claim that they don't need or run well with 48 pilots.
All I can say is mine and the ones I have tuned seem to like them.

As a side note, I know the UK spec bikes came stock with 48s (can't say for sure about other countries) from around 2000 on, so take that for whatever it is worth.
Hawk.... do you have notes to go along with dyno graphs on a specific bike?

Im finding the set up suggested to be way rich, and I'd love to see the measured AFR on other bikes using your prefered set up.

Thanks
Old 09-03-2014 | 12:52 PM
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Originally Posted by CrankenFine
What is your elevation ASL?
Im pretty much at sea level.
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