Go Back   EcoModder Forum > EcoModding > Motorcycles / Scooters
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 01-16-2015, 10:08 PM   #11 (permalink)
Ol' Skooler
 
jcp123's Avatar
 
Join Date: Jul 2009
Location: Tyler, TX
Posts: 1,166

Beater Echo - '00 Toyota Echo
90 day: 42.67 mpg (US)

Hondizzle - '97 Honda Civic DX
Team Honda
90 day: 46.51 mpg (US)
Thanks: 66
Thanked 196 Times in 167 Posts
I'd go with a small accelerator pump...most carbs probably dump too much fuel.

__________________



'97 Honda Civic DX Coupe 5MT
'00 Echo - dead 2/17
'14 Chrysler Town + Country - the better half's car
'67 Mustang Convertible - gone 1/17
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 01-19-2015, 04:54 PM   #12 (permalink)
EV convert
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 8,783

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 212
Thanked 2,897 Times in 2,261 Posts
About the only thing you will find with a carb that will work with out an accelerator pumps a chain saw. You rev them up to speed at almost no load and go to work, unlike a vehicle that has to do a lot of work to accelerate you up to speed.
Another way you can run with out an accelerator pump is to run your carb catastrophically rich.

Years ago I set my Camaro to run a lean idle after I installed a wide band O2 gauge. One day I was changing out accelerator pump jets and forgot to reattach it to the linkage. I started the car, put it in drive and as soon as I touched the gas it died and I figured I forgot to reattach the accelerator pump more or less immediately.
Now a few years before that, I was messing with that car, when it was running really rich before I had a wide band O2 gauge and deluxe carb tuning set and disconnected the accelerator pump to see if it would go and it kind of did. But it was more or less undriveable with no accelerator pump.
__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Old 01-20-2015, 05:42 AM   #13 (permalink)
EcoModding Apprentice
 
adam728's Avatar
 
Join Date: May 2008
Location: Michigan
Posts: 160

Mazda3 - '08 Mazda 3 S
90 day: 29.65 mpg (US)

DR650SE - '13 Suzuki DR650SE
90 day: 46.16 mpg (US)

Wife's - '12 GMC Terrain SLE-2
Thanks: 2
Thanked 22 Times in 18 Posts
Quote:
Originally Posted by oil pan 4 View Post
About the only thing you will find with a carb that will work with out an accelerator pumps a chain saw. You rev them up to speed at almost no load and go to work, unlike a vehicle that has to do a lot of work to accelerate you up to speed.
You'll be hard pressed to find any 2 stroke out there with an accelerator pump, not just chain saws.
__________________
  Reply With Quote
Old 07-23-2015, 07:42 PM   #14 (permalink)
EcoModding Apprentice
 
Join Date: Jan 2012
Location: pittston, pa
Posts: 164

hawk - '78 honda cb 400t hawk II

accent v2 - '11 hyundai accent gl
Thanks: 4
Thanked 5 Times in 3 Posts
sorry to revamp an old tread but i have rebuilt my carbs 2 times already and i still have a gas leak at the accelerator pump cover and area. im at about wits end with this carb. lol sadly i sold the donor no pump carb. if i went with a new donor bike without a accelerator pump what should i adjust to make it work (carb jetting etc .
  Reply With Quote
Old 07-23-2015, 08:04 PM   #15 (permalink)
Master EcoModder
 
Join Date: Apr 2011
Location: Europe
Posts: 364

ZX - '97 Citroen ZX Monaco
OldContinents
90 day: 61.05 mpg (US)
Thanks: 8
Thanked 31 Times in 25 Posts
Quote:
Originally Posted by oil pan 4 View Post
About the only thing you will find with a carb that will work with out an accelerator pumps a chain saw.
Some 4-stroke scooters don't have accelerator pump, I guess design is adjusted to that.

I have one of such carb, it doesn't die when giving throttle, there just is not much happening, not even at WOT.

Slide in that is huge, but throat is much smaller than what slide is, it is like if they would of put twice too big slide to that carb.

When exploring world of cheap chinese scooters, there are no thing that is impossible, no matter how much against logic some design is, some of them has tested it and managed to sell who knows how much of that junk.

----

If there is a leak near accelerator pump, is it sure that it is not the shaft that goes to pump which is worn so that it leaks from there and then just run off to area of cover?
__________________

  Reply With Quote
Old 07-23-2015, 09:42 PM   #16 (permalink)
EcoModding Apprentice
 
Join Date: Jan 2012
Location: pittston, pa
Posts: 164

hawk - '78 honda cb 400t hawk II

accent v2 - '11 hyundai accent gl
Thanks: 4
Thanked 5 Times in 3 Posts
the design is its built into the carb float bowl. its leaking when i pump the throttle even when its not running. and its leaking from the cover. i am going to give it one more try and replace the pump again and this time take the float bowl and clean the crap out of it. or maybe ill buy a new float bowl to see if maybe it cracked
  Reply With Quote
Old 08-05-2015, 09:56 AM   #17 (permalink)
Master EcoModder
 
Join Date: Feb 2009
Location: France - Paris
Posts: 762

la_voiture_de_courses - '03 Renault Megane Estate
OldContinents
90 day: 44.34 mpg (US)

xiao lan - '01 Audi A2
90 day: 38.88 mpg (US)

Brit iron - '92 Mini Mini
90 day: 45.5 mpg (US)

Prius - '09 Toyota PRIUS Lounge
90 day: 47.37 mpg (US)

Beemer - '06 BMW F800 ST
90 day: 53.06 mpg (US)
Thanks: 188
Thanked 33 Times in 30 Posts
If there is no actual accelerator pump, there is an inbuilt system doing the exact same purpose like on CV carbs with the raise of the needle is slowed down when the throttle is opened so that the engine draws more fuel due to being air starved.
__________________
  Reply With Quote
Old 08-05-2015, 04:23 PM   #18 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 8,202
Thanks: 0
Thanked 896 Times in 793 Posts
Most motorcycle and small stationary engine carburettors I've messed with had no accelerator pump. Anyway, after seeing some older cars getting adapted with motorcycle carburettors, I wouldn't be so worried about not having an accelerator pump.
  Reply With Quote
Old 08-05-2015, 04:33 PM   #19 (permalink)
Master EcoModder
 
Join Date: Sep 2009
Posts: 5,927
Thanks: 877
Thanked 2,018 Times in 1,302 Posts
I always like the Hitachi SU types on the first 1970 Datsun 240z (11-69 first month produced).

Float height check using a small plastic straw down the vent hole in the float chamber.

Choke just dropped the seat where the needle moved, no real choke butterfly.

Throttle response was magnificent when they were set up right.

Different tapered needles for different performance parameters.

Two adjustments, the same seat the choke moved and the viscosity of the air chamber oil, with ATF the lightest.

Plugs ran as clean as fuel injection and mileage was as good or slightly better.

It did have a summer winter flap, manually adjusted only from the engine compartment, that you had to use when it got below 40-50 or it fell flat on it's arse when you hit the gas in winter.

You could set it to run too lean, then just add some choke for more power (redneck lean burn).

regards
mech
  Reply With Quote
Old 08-05-2015, 04:38 PM   #20 (permalink)
It's all about Diesel
 
cRiPpLe_rOoStEr's Avatar
 
Join Date: Oct 2012
Location: Porto Alegre, Rio Grande do Sul, Brazil
Posts: 8,202
Thanks: 0
Thanked 896 Times in 793 Posts
Those Hitachi, SU, Stromberg-CD and Keihin-CV carburettors are awesome.

  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2020, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com