Post big bore tuning+all my Newb questions

Does your Spree/Elite already run great, and you're trying to make it quicker/faster? Need a monster motor swap? Discuss your ideas here.

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Jonadz
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Re: Post big bore tuning

Post by Jonadz »

After some long weekend tinkering and trial/error I'm convinced my pilot jet is clogged, both carbs I have, original and new are acting the same way, starts great, runs awesome, warms up and bottom end power vanishes! I'm guessing the reason it runs great cold is the by starter is open allowing more fuel, it closes and so does the supply! Still Havnt been able to get the idle above "almost dying" which would lead me to believe it's clogged. Now I've tried cleaning both, all attempts have left me not able to get air to come out of the "pressed" brass piece the runs parallel to the main jet. When I spray carb cleaner into any other end it will eventually dribble out of the brass but never flow. Any suggestions guys?
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eclark5483
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Re: Post big bore tuning

Post by eclark5483 »

Sound like you got a couple of stubborn little buggers. Time to get out the hard hitting stuff and soak it in "CASTROL SUPER CLEAN" overnight, RINSE, BOIL, SPRAY WITH BRAKE CLEANER, SOAK AGAIN, RINSE AGAIN, BOIL AGAIN, BRAKE CLEANER AGAIN... DONE.
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eclark5483
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Re: Post big bore tuning

Post by eclark5483 »

Other things you can soak it in, are Kerosene, and paint sprayer cleaner. OxyClean works well too. Most carb cleaner products sold today are junk.
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Re: Post big bore tuning

Post by Jonadz »

Alrighty, the trick is just keep doing it! Will pull em back out tonight and have at them! Should I feel a good flow out of the brass if blowing through the air box side hole with the screw in enough to plug up the other side.
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eclark5483
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Re: Post big bore tuning

Post by eclark5483 »

Just remember to soak them overnight so it really breaks down all that gunk. If you boil it in OxyClean, you should see little chunks of gunk start floating up. Other things I have heard of is soaking it in a small crockpot on low using Pine-sol. YES PINE-SOL. Wouldn't advise using the crockpot again for anything else, but as small as a Spree carb is, you can easily submerge it in a tiny crockpot with some pinesol overnight and have it clean as a whistle. Just remember to spray it out with WD-40 first before trying it out.
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Re: Post big bore tuning

Post by Jonadz »

The original is cleaned out and soaking ath the moment but I managed to get the new (not OE) one working right, took an aresonal of chemicals and constant air @90psi but it's flowing! To my amazement I'm getting full adjustment on the carb to! Weird to say it but Wd40 was actually the one that did the trick, low pressure and thick oil substance managed to unclog the jet? Go figure. Now to make it to meatballs this weekend to swap crank cases and I think I'll be done finally!
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benji
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Re: Post big bore tuning

Post by benji »

Wd40 is a good cleaner if you let it sit for awhile. I'm thinking about getting one of those harbor freight parts cleaner bins or maybe a used hot tank from a mechanic's shop.
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Re: Post big bore tuning

Post by Jonadz »

I used an old jetboil system I retired a few years ago, just big enough to drop the carb in, covered with dish soap solution first and simmered for 5 minutes, blew it out then did an oxyclean solution for 5. Rinsed with carb cleaner then brake cleaner. Seemed to really open stuff up.
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eclark5483
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Re: Post big bore tuning

Post by eclark5483 »

I use a tiny crockpot. You can get them so cheap from Wal-Mart or most used goods stores.
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Re: Post big bore tuning

Post by Jonadz »

I'm just going to keep adding to this thread, I feel like I started to many already! So last night had a few minutes so I decided to take her for a spin, started first starter engagement, reved up during warm up, idled down, hopped on, took of great and cleanly accelerated from start to 35. Problem is I didn't feel the powerband? Usually around 15-17 it opens up. Gone? With a couple
laps I tried different positions on the throttle to find the sweet spot and no luck? What would cause the powerband to vanish? Cool having a clean acceleration but that powerband is needed for a few of the hills in my area to maintain 25mph? Suggestions guys? Tuning issue maybe? What actually feeds the powerband? Is it when both low and high jets are combined? Carb leaning itself out? Still new here so just trying to get a better understanding.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

What hole configuration do you have, and what main jet? Would it be accurate to describe your acceleration like the one in this dyno video starting at about 15mph?

https://www.youtube.com/watch?v=TybDRKmT7Fo

If so, what you are experiencing is the BBK at probably it's best tune without upgrading the intake system. A better intake/reeds will really start to open it up. You can possibly help it by either up jetting or down jetting the main, if your up for it, try doing both and report back how it runs. Would be helpful to everyone. If it were me, I'd start with a down jet to something in the low 80's. Downjetting has not been tested, but is a very plausible idea given that the bump in displacement has only went from 50cc to 68cc.

Taz offers the #80 for 5 bucks. Cheap investment to test out a theory if you like: http://www.ebay.com/itm/HONDA-SCOOTER-N ... 2435889885
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

Working in a boiler room so can't load YouTube. Hole configuration is all 3 open currently, main jet is 85. Big problem is the power band was there the day before, boy was it there, only change made was pilot jet was finally cleared completely and my bike will now idle without throttle. This happened before but it was a rich condition I later fixed. (Upon cleaning carb top to bottom I put the clip back rich on the needle without realizing) so my first thought was to lean this out a bit but the thought makes me think sieze and I'm hesitant.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

Try the easy path first, plug up 1 or 2 holes. Create more suction.
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

Will do
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

When you do it, do it with the bike nice and warmed up and give it a fair rating of performance. If performance goes down or remains the same taping off 1 hole, take note, then try again with plugging off 2. If it's the same as the first test, then keep both holes taped up. If performance decreases, then use only 2. Your best stoich air/fuel ratio is obtained when the airbox is able to create suction, and your fuel/oil mix ratio coming from carb is right for the added BBK displacement. Tune DOWN first, not up. "I THINK I'M RICH" seems to be the common error and misconception. Yes, you probably are rich, but not on lubrication or tank oil mix. You are rich on the amount being pumped to the weak intake system. Don't mess much with that airbox, it can probably run the BBK with no holes drilled. Just match up a lower main jet for the system and keep it stock. You kinda have no choice at this point, but let the limitations of the intake/reed system dictate the main jet size. That's somewhere between a #68 which is the largest Honda offered, and the #85 you currently have. Focus there, and you'll be alright. Remember, you want the idle/pilot a bit leaner then what it's gonna do when the main kicks in. The pump will get you to rich when you need it and keep pumping the slower the engine goes, unlike the carb.
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