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1986 honda spree 48mm bbk install,lost a little top end??

Posted: Sun Sep 26, 2010 6:13 pm
by ascmlaren53074
hi i have a 1986 honda spree just had the 48mm bbk installed ,it seems to accelerate quicker but seems like i lost a little top end from 31 to 28 mph, but also it sems like when i floor it all the way it loses a little power but when i ease back on it just a hair it seems to gain a little, whats up with this??(just had the bbk installed a few days ago. thanks

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Sun Sep 26, 2010 7:23 pm
by Bear45-70
Vacuum leak somewhere or a fuel restriction in the carb or fuel feed system.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 2:03 am
by tazland001
Could be the 100 jet is a bit rich. Might want to try a 90.

Taz

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 2:21 am
by Bear45-70
Yeah, or the 100 could be too lean and he needs a bigger jet with his setup. He doesn't mention exhaust or intake setup at all. What does the plug look like after running this thing at speed?

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 11:11 am
by tazland001
I agree the plug is a good place to look. You took the words right out of my mouth Bear. lol

Taz

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 3:03 pm
by zuphilius
Isn't there a break-in period when installing this? He says he just put it on a few days ago.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 3:17 pm
by Bear45-70
True and with that in mind, COMPRESSION CHECK!

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 6:27 pm
by ascmlaren53074
break in is crutial i will wait a couple more weeks and finish the break in period i did not mention that the mechanic took the foam air filter all the way out and dis carded(not sure why he threw it away) would that help a little if it had the air filter back in???? thanks guys for all the replys

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 6:38 pm
by evilone
ascmlaren53074 wrote:break in is crutial i will wait a couple more weeks and finish the break in period i did not mention that the mechanic took the foam air filter all the way out and dis carded(not sure why he threw it away) would that help a little if it had the air filter back in???? thanks guys for all the replys
Yes, you're probably getting too much air now. Bear saying the 100 jet might be too small for your setup would be correct.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 7:10 pm
by patthesoundguy
I certainly wouldnt want break in a big bore kit with no air filter.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 8:48 pm
by ascmlaren53074
i agree, not going to ride it til i get my air filter put back in

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 9:14 pm
by Wheelman-111
Greetings:

The mechanic likely found the filter crumbling in his fingers. My 2001 was doing that when I first purchased Flash 3. The stock engine tried to inhale a chunk of it, producing an early stall scare.

Hopefully a new stock replacement can be sourced. If not, you can try a heavily-oiled UNI 1" pod with that 100 jet. The small Pilot circuit built into the stock carb may remain an issue.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 10:06 pm
by ascmlaren53074
i found a nos filter on ebay just bought it :2thumbs:

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 10:10 pm
by Trafficjamz
You are using the stock airbox on a 48mm bbk? :eyeroll:

That would be your first problem.

Re: 1986 honda spree 48mm bbk install,lost a little top end??

Posted: Mon Sep 27, 2010 10:24 pm
by ascmlaren53074
yes but it had holes drilled in to the top as per the instrutions, but i tried to used a small cone oil breather filter fastned it to the carb and the moter sputtered and missed when you gave it throttle but hooked it back up to the stock air box and it ran better