The Sportster and Buell Motorcycle Forum - The XLFORUM®
 

Go Back   The Sportster and Buell Motorcycle Forum - The XLFORUM® > SPORTSTER MOTORCYCLE FORUM > Sportster Motorcycle Era Specific and Model Specific > Ironhead Sportster Motorcycle Talk (1957-1985)
XLF Blogs XLF Arcade XLF Disclaimer/Privacy Statement/Terms Of Use

Notices

Ironhead Sportster Motorcycle Talk (1957-1985) For all those that wanna talk about Ironhead Sportster Motorcycles

Active Threads
0 Cams, what are the specs?
Last Post: sportytrace
Posted On: 14 Minutes Ago
Replies: 1
Views: 32
0 Anyone go racing last weekend?
Last Post: cycowrencher
Posted On: 34 Minutes Ago
Replies: 2,800
Views: 255,765
5 1200 or 883
Last Post: Bone
Posted On: 41 Minutes Ago
Replies: 982
Views: 294,305
0 Hot Rods, Rat Rods, and Customs.
Last Post: jharback
Posted On: 44 Minutes Ago
Replies: 2,681
Views: 229,865
0 Roads I'd like to ride.
Last Post: Stairman
Posted On: 1 Hour Ago
Replies: 472
Views: 22,628
0 Hottie of the day, no nudity.
Last Post: Stairman
Posted On: 1 Hour Ago
Replies: 8,104
Views: 623,914
0 Official XL Forum Random Image Thread (NO NUDITY!)
Last Post: Stairman
Posted On: 1 Hour Ago
Replies: 41,583
Views: 6,392,506
0 New T Shirts
Last Post: Glamazon
Posted On: 1 Hour Ago
Replies: 6
Views: 122
0 How many miles do you have on your rubbermount?
Last Post: Glamazon
Posted On: 2 Hours Ago
Replies: 389
Views: 72,572
0 New from Pasco, Fl
Last Post: shanneba
Posted On: 2 Hours Ago
Replies: 4
Views: 56
0 What did you do for your sporty Today?
Last Post: Glamazon
Posted On: 2 Hours Ago
Replies: 5,384
Views: 608,206
5 Your worst car?
Last Post: jharback
Posted On: 3 Hours Ago
Replies: 212
Views: 23,267
0 hello and help
Last Post: jharback
Posted On: 3 Hours Ago
Replies: 6
Views: 106
0 New from Reno
Last Post: jharback
Posted On: 3 Hours Ago
Replies: 11
Views: 172
0 XR1200 caliper to 03 883R
Last Post: 93Sportytorres
Posted On: 4 Hours Ago
Replies: 3
Views: 328
0 New England 2018
Last Post: tvon
Posted On: 4 Hours Ago
Replies: 196
Views: 10,171
0 Proposed clutch spring improvement0
Last Post: Serious Blac
Posted On: 4 Hours Ago
Replies: 8
Views: 177
0 Ignition module screws, need size
Last Post: rejeanprimeau
Posted On: 5 Hours Ago
Replies: 16
Views: 303
0 Iree's jukbox joint
Last Post: ~Grind~
Posted On: 5 Hours Ago
Replies: 4,880
Views: 269,386
0 "S" model specific Q&A
Last Post: Hippysmack
Posted On: 5 Hours Ago
Replies: 1,800
Views: 340,498
0 Let's study the 77-85 oil pump, parts, and changes and when.
Last Post: Hippysmack
Posted On: 6 Hours Ago
Replies: 32
Views: 1,491
0 Small nail in tire?? plug or replace
Last Post: rider61
Posted On: 7 Hours Ago
Replies: 130
Views: 18,887
0 Possible Stator Issues?
Last Post: JBaker
Posted On: 8 Hours Ago
Replies: 19
Views: 846
0 To hone, or not to hone
Last Post: T_worth
Posted On: 8 Hours Ago
Replies: 4
Views: 147
0 Cut Wiring, no spark.
Last Post: IXL2Relax
Posted On: 8 Hours Ago
Replies: 3
Views: 86
0 Boardtracker Project
Last Post: JonesL
Posted On: 9 Hours Ago
Replies: 565
Views: 100,617
0 You asked for it! "The Tess' Coffee Thread"
Last Post: sportytrace
Posted On: 10 Hours Ago
Replies: 10,296
Views: 697,077
0 THE Trainspotting Thread
Last Post: trainman
Posted On: 10 Hours Ago
Replies: 2,102
Views: 233,914
0 My take on the world ~ Photo by Trace
Last Post: Stairman
Posted On: 10 Hours Ago
Replies: 835
Views: 92,311
0 DK's Definitive Ride Report - Some of the Best Scenic Roads Out West - Tons of Photo'
Last Post: RandyMac
Posted On: 10 Hours Ago
Replies: 134
Views: 6,963
More...
Members Birthdays
DaddyJay, sixshooter (71), cartoad2001 (69), Dirty Ernie (63), bri1200c (55), pquirk (52), GOTWA (49), gremlinsteve (49), lbowles2 (47), Guess (39), rnaway22es, landon283 (30)
Sponsored Links
Reply
 
Share Thread Tools Display Modes
  #781  
Old 5 Days Ago
brucstoudt's Avatar
brucstoudt brucstoudt is offline
Senior Master Custom Bike Builder
 
Join Date: May 2010
Location: Pottstown PA.
Posts: 12,655
Sportster/Buell Model: xlch
Sportster/Buell Year: 1960
Reputation: 167420
brucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant future
Default

I hope you mean .018.
__________________
72 1000cc barrels and heads, s&s 41/2'' flywheels, sifton cams, s&s super B w/ zippers thunderjet w/yost powertube, andrews gears,and shafts, competition engineering kevlar wet or dry clutch, 72 oil pump, morris magneto w/auto advance and single fire module, cycle electric generator w/electronic regulator,73 cu.in.
Reply With Quote
  #782  
Old 5 Days Ago
RKN's Avatar
RKN RKN is offline
Flat Track Champion
 
Join Date: May 2010
Location: Russia
Posts: 625
Sportster/Buell Model: 883 (90")
Sportster/Buell Year: 2004
Sportster/Buell Model #2: XLCH
Sportster/Buell Year #2: 1974
Reputation: 20095
RKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to all
Default

Yes, sorry, .018". FSM says .015-.025", but is it OK for my engine?
Reply With Quote
  #783  
Old 5 Days Ago
RKN's Avatar
RKN RKN is offline
Flat Track Champion
 
Join Date: May 2010
Location: Russia
Posts: 625
Sportster/Buell Model: 883 (90")
Sportster/Buell Year: 2004
Sportster/Buell Model #2: XLCH
Sportster/Buell Year #2: 1974
Reputation: 20095
RKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to all
Default

I should add I'm using Dytch/Axtell forged pistons and Hastings rings. Corrected CR should be around 8:1.
Reply With Quote
Sponsored Links
  #784  
Old 5 Days Ago
RKN's Avatar
RKN RKN is offline
Flat Track Champion
 
Join Date: May 2010
Location: Russia
Posts: 625
Sportster/Buell Model: 883 (90")
Sportster/Buell Year: 2004
Sportster/Buell Model #2: XLCH
Sportster/Buell Year #2: 1974
Reputation: 20095
RKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to all
Default

On Hastings site, they recommend a minimum gap of .0035" per inch of bore diameter, in my case it will be 3.375 * .0035 = .0118". But that recomendation is probably for automobile engines and probably 3 ring pistons. Found some other recomendation on .0050" for forged pistons, in that case the gap should be 3.375 * .005 = .0169".

Another thing that should be taken into account - that will be a kick only engine. I was reading the forum and came across Dr Dick's post that he was using Total Seal rings in his 5" kick only stroker and had to go back to regular rings because it was really hard to kick start the motor.

So a small gap is bad anyway - there's a risk of ends of the ring touching each other due to expansion from high temperatures and it also makes kick starting the bike harder due to increased cranking pressure.

So what gap size is optimal in my case?
Reply With Quote
  #785  
Old 4 Days Ago
brucstoudt's Avatar
brucstoudt brucstoudt is offline
Senior Master Custom Bike Builder
 
Join Date: May 2010
Location: Pottstown PA.
Posts: 12,655
Sportster/Buell Model: xlch
Sportster/Buell Year: 1960
Reputation: 167420
brucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant futurebrucstoudt has a brilliant future
Default

my experience is with S&S.their end gap specs are so close to the fsm specs. you posted,it's not worth posting.
Reply With Quote
  #786  
Old 3 Days Ago
mrmom9r's Avatar
mrmom9r mrmom9r is offline
XL FORUM TEAM MEMBER
 
Join Date: Jan 2011
Posts: 2,016
Sportster/Buell Model: dragbike
Sportster/Buell Year: 1960
Reputation: 128016
mrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud ofmrmom9r has much to be proud of
Default

Just make sure you have plenty. .018" is not a bad number for a 2 ring piston.

One compression ring means that ring has to do the job of 2 when it comes to carrying heat away from the piston, i.e. it's going to grow more.

There's no measurable performance difference between .010" and .020" so make sure you have plenty.
Reply With Quote
  #787  
Old 3 Days Ago
RKN's Avatar
RKN RKN is offline
Flat Track Champion
 
Join Date: May 2010
Location: Russia
Posts: 625
Sportster/Buell Model: 883 (90")
Sportster/Buell Year: 2004
Sportster/Buell Model #2: XLCH
Sportster/Buell Year #2: 1974
Reputation: 20095
RKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to allRKN is a name known to all
Default

Thank you, Don!
Reply With Quote
Reply

Bookmarks


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Sponsored Links
All times are GMT +1. The time now is 12:13.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2018, vBulletin Solutions Inc.
XL Forum® - Linson Media LLC