SuzukiSavage.com - Pump or non-pump carburetor?

Cavi Mike Serious Thumper Offline Thumper n00b Posts: 1005 Rochester, NY Gender:	Pump or non-pump carburetor? 11/02/12 at 05:09:17 I've decided on a Mikuni TM36 carb and I see they have a pumper option for this specific carb. Any thoughts either way to help make my decision easier?
Back to top	IP Logged

verslagen1 YaBB Moderator ModSquad Online Where there's a will, I want to be in it. Posts: 28790 L.A. California Gender:	Re: Pump or non-pump carburetor? Reply #1 - 11/02/12 at 08:58:12 iffn you got a choice, pump it the pump is meant to smooth out the transition from 1 range to another. Certainly does help in a sudden WOT. Check out truckinduc's thread, he had a HD transplant I think.
Back to top	Versey's Place Tech Section Index IP Logged

Dave YaBB Moderator ModSquad Offline SuzukiSavage.com Rocks! Posts: 17835 Camp Springs, Kentucky Gender:	Re: Pump or non-pump carburetor? Reply #2 - 11/02/12 at 09:01:33 My 4 stroke trials bike has an accelerator pump built into the needle jet. If you crack the throttle fast......it just goes like it is supposed to. No cough, gag, or Aaack like 4 stroke bikes could do in the old days.
Back to top	Someday I will be old......But not today! IP Logged

Cavi Mike Serious Thumper Offline Thumper n00b Posts: 1005 Rochester, NY Gender:	Re: Pump or non-pump carburetor? Reply #3 - 11/02/12 at 14:58:15 Does it sound like it's worth an extra $100? The TM36-2(non-pump) is $150, the TM36-68 pumper is $250. I know I'd really like the extra kick in the arse off the line with the pumper but I guess I'm trying to justify $100.
Back to top	IP Logged

verslagen1 YaBB Moderator ModSquad Online Where there's a will, I want to be in it. Posts: 28790 L.A. California Gender:	Re: Pump or non-pump carburetor? Reply #4 - 11/02/12 at 15:19:03 Depends... are we ever going to ride together? Yes? then no not worth it.
Back to top	Versey's Place Tech Section Index IP Logged

Cavi Mike Serious Thumper Offline Thumper n00b Posts: 1005 Rochester, NY Gender:	Re: Pump or non-pump carburetor? Reply #5 - 11/02/12 at 16:02:26 Ha. Kick in the arse. I get it.
Back to top	IP Logged

SinglesGoinSteady Full Member Offline SuzukiSavage.com Rocks like Bon Scott! Posts: 130 From Seattle, now in Savannah. Gender:	Re: Pump or non-pump carburetor? Reply #6 - 11/02/12 at 17:17:58 How do they work, do they need an electrical lead? Or where does the pump power come from?
Back to top	http://rycatracker.blogspot.com/ IP Logged

Gyrobob

Serious Thumper

Offline

Posers ain't
motorcyclists

Posts: 2571
Newnan, GA
Gender: male

Re: Pump or non-pump carburetor?
Reply #7 - 11/13/12 at 05:35:52

The pump is small. When you crack the throttle, a little diaphragm moves a bit, squirting a momentary jet of fuel into the air flowing through the carb.

Here's a good explanation of the Keihin carb's system. The Mikuni's is similar, but I couldn't find a good explanation. The priniciples are the same. http://www.thumperfaq.com/mxa_ap.htm

Here's a video:
http://www.youtube.com/watch?v=zsqMAMFle0k

The accelerator pump carbs are quite costly, and if the diaphragm gets mucked up, it costs maybe $200 for another diaphragm kit. Usually, though, a proper disassembly and cleaning will fix most acclerator pump malfunctions.

Back to top

If you think there's good in everyone, you haven't met everyone.

IP Logged

Cavi Mike Serious Thumper Offline Thumper n00b Posts: 1005 Rochester, NY Gender:	Re: Pump or non-pump carburetor? Reply #8 - 11/13/12 at 09:32:18 You'd be better off researching what a pumper is on a car carburetor. I'm sure there are plenty of videos on the infamous "Holley double-pumper"
Back to top	IP Logged

Gyrobob Serious Thumper Offline Posers ain't motorcyclists Posts: 2571 Newnan, GA Gender:	Re: Pump or non-pump carburetor? Reply #9 - 11/13/12 at 10:22:12 Cavi Mike wrote on 11/13/12 at 09:32:18: You'd be better off researching what a pumper is on a car carburetor. I'm sure there are plenty of videos on the infamous "Holley double-pumper" Sometimes the pumps in auto carbs are pistons in cylinders, rather than diaphragms.
Back to top	If you think there's good in everyone, you haven't met everyone. IP Logged

Cavi Mike Serious Thumper Offline Thumper n00b Posts: 1005 Rochester, NY Gender:	Re: Pump or non-pump carburetor? Reply #10 - 11/13/12 at 10:57:36 He needs to know what it is and what it does before he learns about different versions of it. Watch closely at the little brass nozzle in the throat, it's the jet for the accelerator pump aka "pumper"
Back to top	IP Logged

Gyrobob Serious Thumper Offline Posers ain't motorcyclists Posts: 2571 Newnan, GA Gender:	Re: Pump or non-pump carburetor? Reply #11 - 11/13/12 at 11:39:32 Cavi Mike wrote on 11/13/12 at 10:57:36: He needs to know what it is and what it does before he learns about different versions of it. That's what the video in reply #7 did.
Back to top	If you think there's good in everyone, you haven't met everyone. IP Logged

v-pilot Senior Member Offline Loud bikes rule! Posts: 257 Rexford NY Gender:	Re: Pump or non-pump carburetor? Reply #12 - 11/13/12 at 17:45:00 Yeah it squirts fuel alright. My '87 Guzzi Le Mans 1000 has a pair of pumped 40mm Dellorto's Makes for a plenty snappy machine but when you chop down on the throttle it takes some time to use up all that fuel you just dumped in there. Just be careful and keep some fingers on the brake lever
Back to top	Suzuki DR650, aprilia RSVR, aprilia Falco, Bimota DB4(2x) Moto Guzzi V10, Ducati 900ss, Triumph Trident, Suzuki LS650 Moto Guzzi Le Mans SE(2x), Moto Guzzi V50, Benelli 250, Ducati 250 IP Logged

SinglesGoinSteady

Full Member

Offline

SuzukiSavage.com
Rocks like Bon
Scott!

Posts: 130
From Seattle, now in Savannah.
Gender: male

Re: Pump or non-pump carburetor?
Reply #13 - 11/14/12 at 22:15:27

Wow, thanks guys. I had searched Mikuni a fair bit online, but, never found an explanation or pictorial of the pumps.

I did read that the flatslides are touchier at low throttle, but, that the pumps on the ones with pumps alleviate that. Some instant throttle response would be nice. Like my buddy's Hypermotard for instance.... ha ha

Cheers -SGS

Back to top

http://rycatracker.blogspot.com/

IP Logged

SinglesGoinSteady Full Member Offline SuzukiSavage.com Rocks like Bon Scott! Posts: 130 From Seattle, now in Savannah. Gender:	Re: Pump or non-pump carburetor? Reply #14 - 11/14/12 at 22:21:27 http://www.youtube.com/watch?v=YvT5Dte33No
Back to top	http://rycatracker.blogspot.com/ IP Logged