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
Over size piston
Avatar
Bola
Swindon
Top Gear User
Site Member
Forum Posts: 125
Member Since:
January 9, 2015
sp_UserOfflineSmall Offline
1
July 9, 2019 - 11:46 am
sp_Permalink sp_Print

Throwing a question out there...

150cc D3 with a +0.6 piston. Would i need to change the jet size from standard?

 

Bike now running OK on tick over however stutters with higher revs. 1st I thought it was the HT earthing out but i have now added heat shrink to the coil to try and insulate it, not 100% sure its fixed. 

Earthing.JPG

 

Maybe its not getting enough fuel at higher revs?

 

Also dies when hot! currently in the process of elimination (Again) thoughts welcome.

sp_PlupAttachments Attachments
Avatar
steve morrison
Co.Durham
Second Gear User
Site Member
Forum Posts: 8
Member Since:
June 13, 2019
sp_UserOfflineSmall Offline
2
July 11, 2019 - 10:07 am
sp_Permalink sp_Print

Would not expect +0.6 would make any difference in fact was not aware you could get this size as normal rebore would be +20 and this would not req a jet size increase maybe put needle up 1 grove and try this out.

Avatar
Bola
Swindon
Top Gear User
Site Member
Forum Posts: 125
Member Since:
January 9, 2015
sp_UserOfflineSmall Offline
3
July 11, 2019 - 1:16 pm
sp_Permalink sp_Print

Woops! +60 not 0.6 rofl(couldn't get +40 piston so had to jump up 1 more)

More fuel, not tried this yet so worth a go!

Tried to cover HT lead to give some insulation too. Points still opening just before optimal piston poison but i have no more movement on the contact breaker housing ( 1/16 in. before top dead centre on D3 i believe).

Stator.JPG

 

Many Thanks

sp_PlupAttachments Attachments
Avatar
steve morrison
Co.Durham
Second Gear User
Site Member
Forum Posts: 8
Member Since:
June 13, 2019
sp_UserOfflineSmall Offline
4
July 12, 2019 - 7:30 pm
sp_Permalink sp_Print

Sounds like fueling issue more than timing issue make sure no air leakage where carb fixed and air way clear via choke ie :choke fully opening.

Avatar
cocorico
Central France
Top Gear User
Site Member
Forum Posts: 2865
Member Since:
June 23, 2013
sp_UserOfflineSmall Offline
5
July 12, 2019 - 8:59 pm
sp_Permalink sp_Print

Bola said
... Points still opening just before optimal piston poison but i have no more movement on the contact breaker housing ( 1/16 in. before top dead centre on D3 i believe).

Points should be opening at 4mm before top dead centre, so you are set somewhat retarded.

1956 D3 in the back of the barn with 6 other bikes ahead of it!

Avatar
Bola
Swindon
Top Gear User
Site Member
Forum Posts: 125
Member Since:
January 9, 2015
sp_UserOfflineSmall Offline
6
July 14, 2019 - 4:36 pm
sp_Permalink sp_Print

Looks like i have movement on the points holder.

Is this common and will it affect the points gap while running?? 

 

If so so how can it be fixed?

674594BA-521A-45AD-B66B-8AE61BA57463.jpeg

Forum Timezone: Europe/London

Most Users Ever Online: 223

Currently Online:
14 Guest(s)

Currently Browsing this Page:
1 Guest(s)

Top Posters:

Cornish Rooster: 3314

Anderzander: 3208

bart: 3142

cocorico: 2865

Sprung Chicken: 2650

Mags 1: 2617

David Dale: 2490

Munchkin: 2223

Blue Heeler: 2139

Katj: 2138

Newest Members:

ths9

Forum Stats:

Groups: 9

Forums: 46

Topics: 11855

Posts: 101757

 

Member Stats:

Guest Posters: 518

Members: 3178

Moderators: 2

Admins: 3

Administrators: Piquet, JMD, Rusty Floater

Moderators: xcgb, Stoo63