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+all my Newb questions

Post by Jonadz »

Ok so tinker time, warmed up and ran around the hood for 20 minutes. first I started playing with the mixture screw, 1/8 turn out, reset idle and would run down the block and back. Ended up noticing the powerband at around 3/4 turns out. Though now it's between 20-25mph, cool for that oh crap moment but not practical where I need it, continued backing out and could feel the powerband timing move with it??? Ended up at about 1 1/4 turns out farther than previously set for a total of 2 1/4 turns out and it ended up engaging at 17 I'd say, gives me the range of 17-25mph with the great torque! Right where I wanted it. New problem, won't go over 30 now. Doesn't bog out, just feels like it is at the end of the line though sure doesn't sound like it! On to air box! Started with the 3 one inch holes and would start covering 1/2 at a time! Ended up with one covered completely and 2 that are half covered. Weird to say but it wouldn't run with 2 completely covered but same space with 2 half covered did great? Guess it would balance intake pressure around the box maybe. Anywho, starts up, idles nice, accelerates rather quickly for what it is, yells "hold your testes" between 17?-25?mph and continues to accelerate on the flat to.... Well atleast 40? No GPS to use at the moment. Takes a decent hill at 25 and doesn't slow down. Think I nailed it for now. Only time will tell.
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Meatball
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Re: Post big bore tuning+all my Newb questions

Post by Meatball »

Without a CHT you're flyin blind. Its vital when tuning/jetting to find that sweet spot. Also, you know to back off the throttle when temps get too high BEFORE seize happens...protect that bore.
I need to find some new haters...the ones I have are starting to like me.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

According to your own picture, you have the equivalent of 1- 1" hole. Please note that for posterity's sake. My advice would be have that 1" hole as close to the inlet as possible. For a more consistent air input. Next step, is testing different main jets. That cost is your own decision, but is advisable. Your AVERAGE JOE setup is more important in getting right then my TOTALLY AWESOME OUT OF REACH parts. If anything, I urge you to keep us all informed on your trials and tribulations.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

One thing I URGE you to note in that video I posted, is my clutch was bad in that run but I was unaware at the time. With "TAZ" gears on an optimal clutch, a Spree should do 35mph at around 6500 rpm. 35 with normal gears is about 8,000rpm, if that is what you have achieved, quit complaining right there, any more is asking more out of the BBK then what is possible on a stock Spree engine.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

My advice.. 1, 1" hole here.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

As you'll see in this image, the 3 holes I drilled in MY airbox, are much smaller. Do the math to figure the total volume. It doesn't take much more air. Notice how close I am to the inlet that you will notice if you flip the airbox lid upside down.
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Jonadz
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

I have a cht and tach on the list of needs to acquire in the future, cht being first and most needed, budget constraints kicked into high gear last night though after I had to pay over $200 to register it at the DOL! Those crooks lol! As for the posterity sake saying 1 one inch hole I didn't want to say that because a single hole didn't work well, but two half blocked did so if anything I would recommend 2 1/2 inch holes. I however didn't try unblocking the one nearest the original inlet and closing the others, I'll play around with that this weekend though. Every motor, bore, elevation, rider size and millions of other variables will always play a role so at best just a baseline for future tinkerers to go off. As for jetting, not a huge rush but will eventually play with at as I currently have no complaints on performance! I was happy with it stock and and more than satisfied with the improvements
made to this point. Current priorities would be a temp gauge, fingers crossed an MLM pipe, then led upgrade on all lights, signal lights are easy but I'm still trying to fab a new headlight, why couldn't the original just be a * rectangle or square!!
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

So for recording purposes
200lb rider
85 spree with 14k "yes 14 thousand" miles with no previous servicing or repairs!
48mm kit with single base gasket and 85 head
Elevation roughly 600ft
Plug gapped at factory spec
85 main jet
New non OE carb with idle, mixture screws, by starter and throttle needle from original OE carb
Needle clip on "normal"
Mixture screw out 2 1/4 from seated
After market coil and plug wire (original cracked)
2 one inch holes half taped on air box
Rear tire 2.75
Drive pulley heavier "86-on" style with kickstart conversion on bad crank with bad gasket only being held together by shear pounds on an impact wrench "crank shaft teeth missing 90%"
New belt
Kevlar lined clutch at factory spec non molested springs
Stock gearing
Oil pump functional with GN2 + 96ish:1 tank mix
Decals removed for weight reduction hahaha!
Cruises 35 with higher speed obtainable.

Will record and report back next week after a weekend meeting at Meatballs place for some upgrades.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

2 - 1/2" holes does not equal 1- 1" hole in terms of volume. Common mistake to make. Do the math on that and prepare to have your mind blown. Otherwise, good info.
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

Good catch Mr Clark, shame on me for under thinking something a Proffesional plumber and former hvac technician should know without thought! A single one inch hole produce a different volume than two 1/2 inch holes so I shouldn't have been confused about different results. I over think and under perform sometimes! In this case however to clarify, a single one inch hole didn't perform as well as 2 1/2 inch openings.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

That's better, but anyway, if you do the math, 2-1/2" holes is LESS volume then 1-1" hole. This should tell you total volume needed is smaller then a 1" opening. Ultraliner if I remember, used a 9 or 9.5mm or something like that, d*** Aussie's anyway (New Zealand actually). But anyways, if your following along, you are finding "less is more", correct? This is the reason I swapped out the 21mm Polini on mine, for a 17mm. The smaller venturi creates better suction. And you haven't even got to the main jet tuning yet, which might lead you back to NO HOLES drilled. The carbs main jets Taz distributes would work great IF you have a proper intake/reed setup, so save the jets, you might need them later, but for sure jet down for now so the intake keeps up. Yes the BBK has more power to give, but you will gain best results with an efficient airfuel intake stream with the proper jet size. You have my 100% Guarantee, you will get a HUGE pickup boost and longer wide open throttle time that way. Your stoich air/fuel ratio should be setting in the mid to lower 12's by that point giving you fuel to spare for it's cooling properties. That is what you should shoot for.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

After a proper jet swap, you should be able to tune air/fuel idle mix screw to somewhere close to OEM spec. 1-1/2 to 1-7/8 turns out. get a tach if you can. You want idle speed set at 1800rpm +/-100rpm. set your best mix setting at that rpm. If the back wheel starts spinning when you reach 1800, then you have weak clutch springs and they should be replaced with Yellow Leo Vince Jog springs.
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eclark5483
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Re: Post big bore tuning+all my Newb questions

Post by eclark5483 »

Jonadz
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Re: Post big bore tuning+all my Newb questions

Post by Jonadz »

Spent a successful Sunday at meatballs place swapping cases and shooting the breeze. Stand up guy right there, learned a lot while sponging as much as I could. Stock Spree with Taz gears is rediculous! My sons big wheel has more go lol. Swapped the bbk into it when I got home and made a world of difference! Going to get this going only adding a temp gauge and run it for this summer then guess what.... Elite swap! I told myself I wouldn't ride his, I knew what it would do, make me want MORE! He convinced me and WOW! Forgot how torquey it was and almost did a backflip coming out of his neighbor hood, if it had wings I would have been airborn.
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