BritBike Forum logo
BritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorBritBike Sponsor SteadfastCyclesBritBike SponsorBritBike SponsorBritBike SponsorBritBike SponsorHepolite PistonsBritBike Sponsor
Upgrade to: Premium Membership | Gold Membership | Life Membership | Vendor Membership | Site Sponsor Membership
Member Spotlight
hacksaw
hacksaw
hamden, ct.
Posts: 972
Joined: January 2002
New BritBike book out!
ShoutChat Box
Comment Guidelines: Do post respectful and insightful comments. Don't flame, hate, spam.
Search eBay for motorcycle parts in following countries
Australia, Canada, France, Holland, Italy, United Kingdom, USA
Random Gallery photo
Manuals on DVD (Shipping included)
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 4 of 4 1 2 3 4
Re: timing the thunderclone the cyclo-bolt, whichever.
Hillbilly bike #826746 10/16/20 4:47 am
Joined: Jan 2014
Posts: 1,011
Likes: 52
N
Britbike forum member
Offline
Britbike forum member
N
Joined: Jan 2014
Posts: 1,011
Likes: 52
Originally Posted by Hillbilly bike
My little mind thinks extremely thin ar filters can cause tuning issues.

+1 definitely.

Support Your #1 BritBike Forum!

Check out British motorcycles for sale: British Motorcycles on e-Bay UK, British motorcycles on e-Bay North America
Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826780 10/16/20 1:20 pm
Joined: Dec 2013
Posts: 5,498
Likes: 77
kevin Online Confused OP
DOPE
OP Online Confused
DOPE
Joined: Dec 2013
Posts: 5,498
Likes: 77
i think anything in front of em will cause flow issuues, even the stock style filter. if there was ever an argument for an airbox, the TBolt is it.

i dont see an advantage in this machine for a mikuni, since the AMAL is in good condition and appears to work correctly. ive taken the machine out and have spent time going up and down the throttle pozitionz to check the mixture. works fine on the needle jet, needle, and slide. no sign of leanness on the 220 when rolling the throttle off but if it works just as well with a 230 ill put one in and leave it.


I would rather be ashes than dust
Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826811 10/16/20 5:25 pm
Joined: May 2013
Posts: 7,193
Likes: 49
Britbike forum member
Offline
Britbike forum member
Joined: May 2013
Posts: 7,193
Likes: 49
230 was the book jetting anyway. So unless your using high density fuel (probably race fuel??) then it should be fine either that.


Now let’s all have a beer beerchug

68’ A65 Lightning “clubman”
71’ A65 823 Thunderbolt (undergoing restoration)
67’ D10 sportsman (undergoing restoration)
68’ D14 trials (undergoing transformation)

Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826820 10/16/20 6:03 pm
Joined: Dec 2013
Posts: 5,498
Likes: 77
kevin Online Confused OP
DOPE
OP Online Confused
DOPE
Joined: Dec 2013
Posts: 5,498
Likes: 77
well, whats in it is indeed left over C12.

110 or so leaded race gas

more testing is indicated


I would rather be ashes than dust
Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826823 10/16/20 6:19 pm
Joined: May 2013
Posts: 7,193
Likes: 49
Britbike forum member
Offline
Britbike forum member
Joined: May 2013
Posts: 7,193
Likes: 49
Density of the C12 according to google is about 0.71, super unleaded in the Uk is about 0.77 so you might find leaner on the jetting is better? (I think I have that right way around) Although it’s not always as simple as that


Now let’s all have a beer beerchug

68’ A65 Lightning “clubman”
71’ A65 823 Thunderbolt (undergoing restoration)
67’ D10 sportsman (undergoing restoration)
68’ D14 trials (undergoing transformation)

Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826849 10/16/20 9:45 pm
Joined: Dec 2013
Posts: 5,498
Likes: 77
kevin Online Confused OP
DOPE
OP Online Confused
DOPE
Joined: Dec 2013
Posts: 5,498
Likes: 77
i dunno. at gawd awful pricing the race gas isnt what i normally use. im juzt finishing off an opened can.

less pounds per gallon of fuel means less O2 needed so yes leaner in indicated. maybe thats why the 220 works. but i still want to put in a 230 and see.

i tried 230 in a 750 commando and the richness was immefiately apparent, iirc

my local service station no longer sells leaded 110 premium. instead theyre filling their tank with non-ethanol 90 octane. thats what i ll be using, i believe.


I would rather be ashes than dust
Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826851 10/16/20 10:17 pm
Joined: Aug 2001
Posts: 5,464
Likes: 69
Britbike forum member
Offline
Britbike forum member
Joined: Aug 2001
Posts: 5,464
Likes: 69
A bigger carb 30 versus 28 will have lower air speed, lower air speed means less lift at the jet, means a bigger jet. better larger than smaller.
Q ( flow ) = Area times velocity, when Q is the same and A is bigger V has to go down, less V means less depression over the jet.


71 Devimead, John Hill, John Holmes A65 750
56 Norbsa 68 Longstroke A65
Cagiva Raptor 650
MZ TS 250
The poster formerly known as Pod
1 member likes this: Allan G
Re: timing the thunderclone the cyclo-bolt, whichever.
kevin #826854 10/16/20 10:25 pm
Joined: Dec 2013
Posts: 5,498
Likes: 77
kevin Online Confused OP
DOPE
OP Online Confused
DOPE
Joined: Dec 2013
Posts: 5,498
Likes: 77
. . . but less dense race fuel will respond with greater lift, all other things being equal . . .nothing is straightforward with carburation. thats why irs so interezting, tuning these things is more art than science

this weekend i will fill it with 90 octane nonethanol pump gas and go find a straight section out here in the country


I would rather be ashes than dust
1 member likes this: Allan G
Page 4 of 4 1 2 3 4

Moderated by  Allan G, Jon W. Whitley 

Link Copied to Clipboard
Home | Sponsors | Newsletter | Regalia | Calendar | Bike Project | BritBike Museum | Spiders Cartoons | DVD- Manuals & Parts books
Upgrade to: Premium Membership | Gold Membership | Life Membership | Vendor Membership | Site Sponsor Membership
Powered by UBB.threads™ PHP Forum Software 7.7.4