BritBike Forum logo
BritBike Sponsor BritBike Sponsor BritBike Sponsor
BritBike Sponsor

BritBike Sponsor

BritBike Sponsor
BritBike Sponsor BritBike Sponsor BritBike Sponsor
  JWood Auction  
Home | Sponsors, Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons, "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
Photo posting tutorial

Member Spotlight
Neal J
Neal J
Boston, MA
Posts: 24
Joined: July 2007
Show All Member Profiles 
Shout Box
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Who's Online Now
208 registered members (2ndchildhood), 1,562 guests, and 558 spiders.
Key: Admin, Global Mod, Mod
Newest Members
Gerard, Regi, Doug Baril, revans, Gilly
9962 Registered Users
Top Posters(30 Days)
btour 186
koan58 101
Stuart 85
NickL 69
Popular Topics(Views)
440,407 mail-order LSR
Forum Statistics
Forums33
Topics65,307
Posts632,163
Members9,962
Most Online3,995
Feb 13th, 2017
Like BritBike.com on Facebook

Previous Thread
Next Thread
Print Thread
Rate This Thread
#528209 - 02/14/14 9:16 pm 71 T120 choke lever position?  
Joined: Dec 2006
Posts: 208
TBolt72 Offline
BritBike Forum member
TBolt72  Offline
BritBike Forum member

Joined: Dec 2006
Posts: 208
Glenwood, Iowa USA
Without giving a lesson on the search function, can someone tell me the correct position of the handlebar mounted choke lever on my newly acquired 1971 Triumph Bonneville (2600 original miles, 100% original)? Im assuming full tension on the cables raises the choke slides inside the carb slides? Or is the lever parallel with the handlebar in the slack position? It will run in both positions, but Im having a hell of a time getting a nice idle in either position. I cleaned the carbs and have clean fuel going to both, new battery, cleaned points and set them, and reset them. Found the advance mechanism was stuck and freed it up, works good now. Thanks [img:center][/img]

Last edited by TBolt72; 02/14/14 9:20 pm.
Support Your #1 BritBike Forum!
Membership Type! Free
Member
Premium
Member
Premium Life
Member
Vendor
Member
Site
Sponsor
Recognition No Premium Member Premium Life member (5 years) Vendor Member Site Sponsor Membership
Post commercial threads No No No Yes Yes
Custom title No Yes Yes Yes Yes
Upload avatar & photos No Yes Yes Yes Yes
Link avatar & photos Yes Yes Yes Yes Yes
Private Message Storage: 10 100 100 100 100
Length of signatures 255 600 600 600 600
Removes this very advert island between post 1&2 No Yes Yes Yes Yes
Price Free $12.90/year $105.00 No End
$55.00/5 years
$210.00/year
($17.50/month)
Email
Click on button >>
  Premium Member Premium Life member Vendor Member Site Sponsor Membership
#528213 - 02/14/14 9:36 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Mar 2006
Posts: 1,165
htown Online content
BritBike Forum member
htown  Online Content
BritBike Forum member

Joined: Mar 2006
Posts: 1,165
Magnolia, TX
Not quite sure how the lever should point on your particular bike but tightening the cable pulls the choke slide up to run position.
If it runs better with the choke down that could mean you are too lean. Did you make sure you got the pilot jet cleaned? Also, need to synch slides. Check float levels.
Here's some good general info:
http://www.jba.bc.ca/Bushmans%20Carb%20Tuning.html


1978 Bonneville T140E
1974 Trident
1970 BSA Thunderbolt
1971 Norton Commando
1972 Norton Commando
2-1974 Norton Commandos
2004 XL 1200R Sportster

Everything will be alright in the end. If its not alright, its not the end.
#528215 - 02/14/14 9:45 pm Re: 71 T120 choke lever position? [Re: htown]  
Joined: Dec 2006
Posts: 208
TBolt72 Offline
BritBike Forum member
TBolt72  Offline
BritBike Forum member

Joined: Dec 2006
Posts: 208
Glenwood, Iowa USA
Great link, thank you.

#528225 - 02/15/14 12:26 am Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Mar 2006
Posts: 1,165
htown Online content
BritBike Forum member
htown  Online Content
BritBike Forum member

Joined: Mar 2006
Posts: 1,165
Magnolia, TX
I keep a supply of the #78 drill bits on hand. Seeing as you have more than one Brit bike you'll need a few. For a handle use some superglue to put one into the end of a plastic squirt tube off an old WD40 can or similar. I order mine here.
http://www.micromark.com/no-78-drill-bits-pkg-of-6,6661.html

Last edited by htown; 02/15/14 12:30 am.

1978 Bonneville T140E
1974 Trident
1970 BSA Thunderbolt
1971 Norton Commando
1972 Norton Commando
2-1974 Norton Commandos
2004 XL 1200R Sportster

Everything will be alright in the end. If its not alright, its not the end.
#528233 - 02/15/14 2:26 am Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Jun 2002
Posts: 9,307
Stuart Online content
BritBike Forum member
Stuart  Online Content
BritBike Forum member

Joined: Jun 2002
Posts: 9,307
Scotland
Hi,

Originally Posted By: TBolt72
the correct position of the handlebar mounted choke lever
Im assuming full tension on the cables raises the choke slides inside the carb slides?

The cable inner is 'round the lever pivot, so the lever position with most inner 'round the pivot has the chokes' positions at their highest? As the cable is parallel to the 'bars, this lever position will be at right-angles to the 'bars? Also, you could remove the air cleaner covers and stick a finger into each carb. to feel for the choke slide?

It's wise to look/stick a finger into each carb. anyway, to check that the choke slide is fully-withdrawn from the venturi - a stretched cable inner stops the slide being withdrawn completely. frown

Once you've established that the choke slides are fully out of the air-stream, you might want to screw the lever pivot down tight and never touch it again - the only one of my Triumphs that still has the chokes is my T150 ... and that's only because the choke lever mounting is part of the brake lever mounting. mad Apart from that, the chokes were nothing but a pita, no help starting or warming up the bike but vibrating on at times I couldn't reach the lever mad (I have a normal-length thumb, rather than the 6"-long one the AMAL choke lever designer had ...). When I built my T100, I didn't even fit the choke components.

Hth.

Regards,

#528237 - 02/15/14 3:21 am Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Apr 2002
Posts: 714
Nick Offline
BritBike Forum member
Nick  Offline
BritBike Forum member

Joined: Apr 2002
Posts: 714
Out There!
Pilot circuits almost certainly plugged.

Easier way to clean pilot circuit: get a .010~.015" steel guitar string (cheap at any guitar shop), remove air screw, push guitar string through until you feel it pass through the air jet at the other end. Then blow some air or brake cleaner through it from the air-screw side. Repeat.

Drilling the jet out a bit larger (as mentioned above) is the best fix, but working with those tiny drills can be a hassle.

If it won't idle (and if there is no significant change when the air screw is turned in and out) pilot circuit is plugged.

Nice bike!

Last edited by Nick; 02/15/14 3:22 am.

When people who should have known better cautioned me about the dangers of motorcycle racing, I always told them that a fear of death is nothing more than a fear of life in disguise.
#528242 - 02/15/14 4:48 am Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Aug 2001
Posts: 6,904
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member

Joined: Aug 2001
Posts: 6,904
scotland
Post up a photo of the choke lever and we'll tell you which way is which.


Amateur Loctite enthusiast.
#528252 - 02/15/14 5:45 am Re: 71 T120 choke lever position? [Re: triton thrasher]  
Joined: Nov 2008
Posts: 2,674
desco Online content
BritBike Forum member
desco  Online Content
BritBike Forum member

Joined: Nov 2008
Posts: 2,674
Bishop, Calif.
Pull the air filters off and look in the carbs while moving the lever.
Chokes should rise and fall together.
The "run" position is the chokes up all the the way.
Most of the time you should only need the to tickle the carbs to start. My 72 has no chokes. My 68 has them and I never use them.
I just think the lever looks cool.

http://www.gabma.us/page2.htm
Here's another good page.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
#528254 - 02/15/14 5:57 am Re: 71 T120 choke lever position? [Re: Nick]  
Joined: Nov 2008
Posts: 2,674
desco Online content
BritBike Forum member
desco  Online Content
BritBike Forum member

Joined: Nov 2008
Posts: 2,674
Bishop, Calif.
Guitar strings are 10 to 14 dollars for 3 and they are not the correct size.
# 78 drill bits are 8 bucks for 6 and they are the correct size.
You are not drilling the jet larger you are cleaning it correctly.


1968 T120R
1972 T120RV
Any advice given is without a warranty expressed or implied.
#528280 - 02/15/14 8:31 am Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Aug 2001
Posts: 6,904
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member

Joined: Aug 2001
Posts: 6,904
scotland
They make 16 thou strings. If you know a player, you won't have to pay anything for enough wire to clean a jet.

Under some circumstances, you might try the wire rather than wait for the drill to arrive in the post.


Amateur Loctite enthusiast.
#528381 - 02/15/14 6:52 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Dec 2006
Posts: 208
TBolt72 Offline
BritBike Forum member
TBolt72  Offline
BritBike Forum member

Joined: Dec 2006
Posts: 208
Glenwood, Iowa USA
Thanks for the replies fellas. I will get some #78 drill bits coming. I have entered this bike in my first show ever (AMCA) and one of the requirements to enter is to start it and it has to run5 seconds. It will do that now, so that will get me in the door. I plan to ride this bike in the Spring so I will pull the carbs off after the show. Thanks again.


#528382 - 02/15/14 7:03 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Mar 2006
Posts: 1,165
htown Online content
BritBike Forum member
htown  Online Content
BritBike Forum member

Joined: Mar 2006
Posts: 1,165
Magnolia, TX
Looks like the way its mounted, rotating it clockwise against the stop will pull the chokes up. You need to pull the air cleaners to check the slide synch anyway so will give you a chance to verify.
Like someone mentioned you probably don't need to use them except maybe when the temp is below about 50F or so. Just tickle'em good.


1978 Bonneville T140E
1974 Trident
1970 BSA Thunderbolt
1971 Norton Commando
1972 Norton Commando
2-1974 Norton Commandos
2004 XL 1200R Sportster

Everything will be alright in the end. If its not alright, its not the end.
#528383 - 02/15/14 7:05 pm Re: 71 T120 choke lever position? [Re: htown]  
Joined: Dec 2006
Posts: 208
TBolt72 Offline
BritBike Forum member
TBolt72  Offline
BritBike Forum member

Joined: Dec 2006
Posts: 208
Glenwood, Iowa USA
Thanks, it starts just fine tickling the carbs. Ive heard of people removing them, so I think I will do that when the carbs come back off.

#528412 - 02/15/14 9:25 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Oct 2008
Posts: 4,861
DavidP Offline
BritBike Forum member
DavidP  Offline

BritBike Forum member

Joined: Oct 2008
Posts: 4,861
Gnashville
Originally Posted By: TBolt72
Thanks, it starts just fine tickling the carbs. Ive heard of people removing them, so I think I will do that when the carbs come back off.

Works well with most. I had a T150v with no chokes, would start even at 30 degrees without them. But, on a triple one can open the all throttles slightly with the screw on the manifold. When my A65 had Amals it gave trouble starting at low temps, would start but it wouldn't stay running.
You will need to plug the choke cable holes in the tops of your carbs after removing the chokes. I guess you could just remove the choke slides and springs, leaving the cables where they are and silicone the ferules in place to satisfy the rivet counters. laugh


Stepping on others doesn't make you stand tall.

71 A65L "Zelda"
92 BMW K100rs "Gustav"
#528420 - 02/15/14 10:03 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Feb 2008
Posts: 4,050
Tridentman Online content
BritBike Forum member
Tridentman  Online Content

BritBike Forum member

Joined: Feb 2008
Posts: 4,050
New Jersey USA
If you want a completely predictable bike-buy Japanese.
If you want a bike with character--buy a Brit bike.
Some of my Brit bikes start fine with tickling and no choke. Others need choke for the first couple of miles otherwise they splutter and misfire in a way to make them virtually unrideable.
Brit bikes are like women--what works with one doesn't work with another --and vice versa.
IMHO--don't remove the chokes until you have used the bike for a good while--only then can you be sure that you don't need them--or find that you do.
HTH

#528430 - 02/15/14 11:05 pm Re: 71 T120 choke lever position? [Re: TBolt72]  
Joined: Mar 2006
Posts: 1,165
htown Online content
BritBike Forum member
htown  Online Content
BritBike Forum member

Joined: Mar 2006
Posts: 1,165
Magnolia, TX
The chokes help sometimes even in mild Houston temps. I'd leave them in. I've even retrofit them on two my bikes. I kind of like to leave things stock if possible unless its a definite improvement.


1978 Bonneville T140E
1974 Trident
1970 BSA Thunderbolt
1971 Norton Commando
1972 Norton Commando
2-1974 Norton Commandos
2004 XL 1200R Sportster

Everything will be alright in the end. If its not alright, its not the end.
#528445 - 02/16/14 1:38 am Re: 71 T120 choke lever position? [Re: DavidP]  
Joined: Jun 2002
Posts: 9,307
Stuart Online content
BritBike Forum member
Stuart  Online Content
BritBike Forum member

Joined: Jun 2002
Posts: 9,307
Scotland
Hi,

Originally Posted By: DavidP
You will need to plug the choke cable holes in the tops of your carbs after removing the chokes. I guess you could just remove the choke slides and springs, leaving the cables where they are and silicone the ferules in place to satisfy the rivet counters. laugh

AMAL can also supply the small screw with the correct thread to fit in place of the cable adjuster in the carb. top.

Hth.

Regards,

#528477 - 02/16/14 10:05 am Re: 71 T120 choke lever position? [Re: htown]  
Joined: Aug 2001
Posts: 6,904
triton thrasher Online content
BritBike Forum member
triton thrasher  Online Content
BritBike Forum member

Joined: Aug 2001
Posts: 6,904
scotland
Originally Posted By: htown
Looks like the way its mounted, rotating it clockwise against the stop will pull the chokes up. .


Yeah, looks set for normal running there.

Move lever outward and forward (anticlockwise) to release the cable and drop the slides for cold starting.

Last edited by triton thrasher; 02/16/14 10:06 am.

Amateur Loctite enthusiast.

Moderated by  John Healy 


Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | "OLD" BritBike Forum | DVD- Manuals & Parts books | BritBike Stickers & Decals
Upgrade to: Premium Membership | Premium Life Membership | Vendor Membership | Site Sponsor Membership
UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.519s Queries: 15 (0.057s) Memory: 0.9303 MB (Peak: 1.2046 MB) Zlib disabled. Server Time: 2017-11-25 05:49:09 UTC