A A A
Avatar

Please consider registering
Guest

Search

— Forum Scope —






— Match —





— Forum Options —





Minimum search word length is 3 characters - maximum search word length is 84 characters

Register Lost password?
sp_Feed sp_PrintTopic sp_TopicIcon
D1 carb
Avatar
Bigpete
Corpach, Fort William
Second Gear User
Site Member
Forum Posts: 7
Member Since:
May 24, 2021
sp_UserOfflineSmall Offline
1
May 27, 2021 - 8:12 pm
sp_Permalink sp_Print

Hi, I've got my D1 fitted with a 361 running and starting ok , but!!, It bogs something terrible of the bottom . I've stripped it, cleaned it and tried the needle in different positions but now I'm back to second from top. Any ideas or suggestions welcome as I'm lost as it's so basic.👍

Highlander, there can be only one!

Avatar
Sponge
Lancashire (A chip shop somewhere near Preston)
Top Gear User
Club Member
Forum Posts: 605
Member Since:
November 6, 2016
sp_UserOfflineSmall Offline
2
May 31, 2021 - 8:52 am
sp_Permalink sp_Print

If it is bogging as you open the throttle from tickover then it is most likely to be the cutaway on the slide. Suggest remove the slide and have a good look to see if it has any numbers etc on it. This will give you a clue.

Avatar
GlenAnderson
Dover
Top Gear User
Club Member
Forum Posts: 409
Member Since:
August 27, 2013
sp_UserOfflineSmall Offline
3
May 31, 2021 - 9:38 am
sp_Permalink sp_Print

It might have the right slide, but be very worn. 

Avatar
Sponge
Lancashire (A chip shop somewhere near Preston)
Top Gear User
Club Member
Forum Posts: 605
Member Since:
November 6, 2016
sp_UserOfflineSmall Offline
4
May 31, 2021 - 10:46 am
sp_Permalink sp_Print

Thats a real possibility but I guess it's best to start by making sure it has the right bits inside it. 

Avatar
sunny
Norfolk
Top Gear User
Club Member
Forum Posts: 1821
Member Since:
January 9, 2013
sp_UserOfflineSmall Offline
5
May 31, 2021 - 11:26 am
sp_Permalink sp_Print

D 1,3&5  used  the slide  to  stut  off  the  engine     i think  the jets  for the  5/8  361   Main 75     .,    needle  jet ,106 ., needle  pos 2  .,.,  slide 5 

Avatar
Bigpete
Corpach, Fort William
Second Gear User
Site Member
Forum Posts: 7
Member Since:
May 24, 2021
sp_UserOfflineSmall Offline
6
June 1, 2021 - 10:47 pm
sp_Permalink sp_Print

Thanks lads, slides a 5 and looks to be brand new. Its a rookie question on Bantam carbs as I've never seen anything so simple which can make it very complicated if you get my drift. 

Needle is on second from top  I don't have the jet numbers but will get them. Plug is a bp7hs, non resistor cap. It's a good starter, second or third kick. Goes really well when you get it of the bottom. Appreciate it's an old bike and carb but I've heard Bantams that are little firecrackers on the throttle with no hesitation.

Highlander, there can be only one!

Avatar
Bigpete
Corpach, Fort William
Second Gear User
Site Member
Forum Posts: 7
Member Since:
May 24, 2021
sp_UserOfflineSmall Offline
7
June 2, 2021 - 3:54 pm
sp_Permalink sp_Print

Checked internals today, 106, 75 jets, new no5 slide and needle on 2nd from top. Carb cleaned out . Took it for a run and it does about 35 flatstick but shut the throttle and near stalls, not keen on ticking over till it's racing.

Is it  possible it's something other than carb, maybe timing out a bit??

Highlander, there can be only one!

Avatar
Unitminor
Norfolk
Top Gear User
Site Member
Forum Posts: 109
Member Since:
February 27, 2018
sp_UserOfflineSmall Offline
8
June 2, 2021 - 5:07 pm
sp_Permalink sp_Print

When you say you shut the throttle are you closing it completely because if you are you will stopping the air going through it in effect you are stopping the engine.  That is the way D1 and D3 stop the engine. 

Avatar
Sponge
Lancashire (A chip shop somewhere near Preston)
Top Gear User
Club Member
Forum Posts: 605
Member Since:
November 6, 2016
sp_UserOfflineSmall Offline
9
June 2, 2021 - 9:19 pm
sp_Permalink sp_Print

A few other things to check are: 

Exhaust clear......not full of carbon

Air cleaner clean......not full of insects etc

Does it have a head gasket ?....if so then remove it...resurface the head and torque it down. 

Air leaks....use bubble solution around the cylinder base and the catb flange

D1s are very tolerant of leaks, poor timing, carbon build up etc and that makes it hard to do fault finding but best advise is to only change one thing at a timeand stick with it until you start to notice improvements...be prepared for it to be several small things rathet than one big thing and plan accordingly. 

If it is any consolation....my D1 only does just over 35 mph flat out but then again I weigh 22+ stones ....it does, however, return 100mpg at average speed of 30mph on a long run and runs very clean through the rev range. My friend, who weighs about 8 stone,  can wring nearly 50 mph out of it so body mass does have an effect. Good luck and work to a system...one thing at a time and you will see positive results.

Avatar
Number6
Lincolnshire
Top Gear User
Club Member
Forum Posts: 508
Member Since:
January 18, 2020
sp_UserOfflineSmall Offline
10
June 2, 2021 - 9:20 pm
sp_Permalink sp_Print
When you say you shut the throttle are you closing it completely because if you are you will stopping the air going through it in effect you are stopping the engine.  That is the way D1 and D3 stop the engine. 

Yes if you want it to have an idle when thottle is 'shut', you have to take all the slack out of the cable, and then a bit more to raise the slide a gnat's (i.e. whatever is needed so that it will idle).

laugh

Mike H --

Murphy's 4th law of motion states that any small object that is accidentally dropped will immediately hide itself under a larger object.

Avatar
Bigpete
Corpach, Fort William
Second Gear User
Site Member
Forum Posts: 7
Member Since:
May 24, 2021
sp_UserOfflineSmall Offline
11
June 3, 2021 - 11:08 am
sp_Permalink sp_Print

Great advice again lads, Thanks very much. Throttle shut to kill I didn't know about and I'm 17 stone so maybe I'm not that far off and just expecting a bit to much. Love the add bike and this forum is a wealth of information.  

Highlander, there can be only one!

Avatar
lbayorkie
North Yorkshire
Top Gear User
Club Member
Forum Posts: 574
Member Since:
December 6, 2016
sp_UserOfflineSmall Offline
12
June 3, 2021 - 11:43 am
sp_Permalink sp_Print

I'm 14st and only get 37mph flat out and based on my first consumption check I achieve 80mpg. 

Avatar
Unitminor
Norfolk
Top Gear User
Site Member
Forum Posts: 109
Member Since:
February 27, 2018
sp_UserOfflineSmall Offline
13
June 3, 2021 - 1:27 pm
sp_Permalink sp_Print

I have set my D3 throttle as number6 said so it ticks over and to stop it I have fitted a old spare horn press button . It is connected to the points so when pressed it earths the points and stop the engine .

Avatar
GlenAnderson
Dover
Top Gear User
Club Member
Forum Posts: 409
Member Since:
August 27, 2013
sp_UserOfflineSmall Offline
14
June 3, 2021 - 10:56 pm
sp_Permalink sp_Print

Worth checking the timing. My D1 bogs down in top unless the road conditions (downhill, following wind) allow me to get over 40, then it picks up again as it revs higher. It will do 53 ish flat out but soon fades away at the first sight of a hill. That’s with a skimmed head and slightly revised timing to make the most of the higher compression. I’m only about 11st though, and that does make a difference. 

Avatar
Number6
Lincolnshire
Top Gear User
Club Member
Forum Posts: 508
Member Since:
January 18, 2020
sp_UserOfflineSmall Offline
15
June 3, 2021 - 11:04 pm
sp_Permalink sp_Print

http://livinginthepast-audioweb.co.uk/imagex/misc/like-button2.jpg

Mike H --

Murphy's 4th law of motion states that any small object that is accidentally dropped will immediately hide itself under a larger object.

Avatar
Bigpete
Corpach, Fort William
Second Gear User
Site Member
Forum Posts: 7
Member Since:
May 24, 2021
sp_UserOfflineSmall Offline
16
June 7, 2021 - 9:58 pm
sp_Permalink sp_Print

Evening all, don't want to speak to soon but I think I may have it sorted. Took the bike out a run and when I came back I took the plug out and it was showing lean. Checked for air leaks and all was good. Ordered a #80 jet , fitted that and lifted the needle to 3rd from top.

all seems good and pickup is good of the bottom with a nice steady tickover. Just to take it a run now and fingers crossed👍

Highlander, there can be only one!

Forum Timezone: Europe/London

Most Users Ever Online: 223

Currently Online:
21 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Top Posters:

cocorico: 3320

Cornish Rooster: 2917

Blue Heeler: 2435

bart: 2428

David Dale: 2144

Sprung Chicken: 2121

Piquet: 1846

sunny: 1821

Mags 1: 1753

mike p5xbx: 1647

Newest Members:

sprayerandy

Forum Stats:

Groups: 9

Forums: 48

Topics: 10628

Posts: 93900

 

Member Stats:

Guest Posters: 1366

Members: 3347

Moderators: 0

Admins: 3

Administrators: Bantam-Super, JMD, Stoo63