| Author | Message | ||
     Gearheaderiko |
Valve springs wont change lift. What will happen is they'll bind or float (the valve). Or the valve wont be long enough or there wont be enough clearance between the keepers, valve guide or seals. If you 'couldnt use the lift fully' then what will happen is the lifters will compress, pushrods will bend or rockers will bend (ie:the extra lift will be taken up somewhere). Thats very useful information, but I think some of it is getting convoluted in the posting. | ||
| Buellistic |
Ezblast: Could you explain a little further "BUT YOU'D GET CLOSE" ... There a lot of us(my self included) that do not quite understand this ALTERNATIVE VIEW/IDEA ??? In BLASTing LaFayette | ||
| Ezblast |
The ratio rockers and the stock cam is like .510 - yet with stock springs your only going to .498 - new, .489 - used - the max the spring will do - so though they would allow more lift, more lift will not happen because the springs won't go further than their design, which is less with age - around 15,000 miles of work. GT - JBOTDS! EZ  | ||
| Gearheaderiko |
Thats not making any sense. You can use lawnmower springs and if they'll travel the full distance, it wont change the lift. Something is getting lost in the translation! Actually with heavier/tighter/new springs you can get less lift because (theoretically) they will compress the stock hydrolic lifter more and the lifter will absorb some of that travel. If you cant get full lift then there is a clearance problem. | ||
| Ezblast |
Old springs will loose lift, fact - called sagging - stock is .5 (.498) - after about 15,000 miles they will be down to .489 - what Aaron measured - the springs are what is going to limit/allow lift. GT - JBOTDS! EZ | ||
| Gearheaderiko |
They will sag just like front fork springs or rear shock springs, but the full travel of your suspension will not change. Same with the valves. If the springs lose 'tension' the valve will still travel (or bottom out) at the same place-maximum lift (or maximum travel). What the springs lose with age is the ability to pull the valve back into the head fast enough to keep up the the cam profile and engine rpm (hence they will float). Something is getting lost in translation. | ||
| Gearheaderiko |
Perhaps what he meant was that a .489 lift is the maximum that can be used with old springs. | ||
| Ezblast |
Max lift aka Valve lift - ok Stock - .475 B50 - .498 B70 - .530 Ammazing what a little lift will do - lol GT - JBOTDS! EZ | ||
| Ezblast |
Erik - you are correct! GT - JBOTDS! EZ | ||
| Buellistic |
BLASTers: CLASS 101 Valves(stock size), valve seats(stock size), valve guides, valve guide seals, rocker arms(stock), and valve springs ... The information on these components are not put in the FACTORY SERVICE MANUALS because they(THE H-D MOTOR COMPANY) does not want technicians to know, for that matter, YOU to know anything about these components ... When a Mechanic does a valve job a valve refacing machine is used to reface the valves and valve seat refacing equipment to reface the valve seats ... The Mechanic checks the valve head and stem to see if it is within SPECIFICATIONS and can be reused and the valve guide also ... Next the valve is placed in the head(valve seat has been redone) ... The distance between the head and valve stem(where the rocker arm pushes to open the valve) if it is with in SPECIFICATIONS ... If the valve stem is too far out, sometimes a new valve will bring it back into SPECIFICATIONS ... If not the valve seat will have to be replaced ... If the seat is replaced the valve stem has to extend out of the head within SPECIFICATIONS, if not the seat will have to be refaced until it does(valve spring binding) ... The Mechanic also checks the valve guide is to be within SPECIFICATIONS ... If not the replacement will have to be checked for proper depth in head if it does not have a step on it where it will only go in the head so far .... If these components are not in SPECIFICATIONS the valve springs will coil bind(valve setm too short) or the valves will float(valve stem too long) ... The valve guide seal is put on the valve guide and keeps oil from being drawn into the combustion camber by way of the valve guide ... Rocker arms, if you want you valve guides (and seals) to last longer you put in the ones with the needle bearing tips ... "BUELLschitte" to those that say they will not last as the tappets have needle bearings so there is no problem ... If you put in 1.75 to one rocker arms, or a high lift cam you should check to make sure the valve springs do not coil bind or valves come too close to close to piston ... That means at max. valve lift you should be able to move the valve in 0.060 before coil binding(this is more for shimimg valve springs than anything else)and only go into the valve pockets of the piston no more than 0.040 away from touching the piston ... Valve spring when compressed to a SPECIFIED LENGHT will exert a SPECIFICATION plus/minus pounds to be good spring ... Not all springs are created equal, so you check them and put the strongest on the intake valve ... In BLASTing LaFayette | ||
| Ezblast |
Clarification - Actually though your valvetrain is capable of more lift, Your still not going to want go past the max they - the springs - can perform, at least not without hurting your driveline - example - you put B70 cams in with stock springs - you can do more lift but the springs can't and all you'll get in the end is valvetrain damage - so yes you can but you don't want to. GT - JBOTDS! EZ (Message edited by ezblast on November 19, 2006) | ||
| Buellistic |
R80rt: There are two ways to jet your CARB., on a DYNO or with a FUELL/AIR GAUGE ... IMHO the FUELL/AIR GAUGE is the REAL LIFE WAY ... With my engine set up: PRODUCT IMPROVED "OEM" air box with a K&N air filter, PRODUCT IMPROVED "OEM" muffler, Timing mark just coming into the timing plug hole, and sparkplug gaped to 0.030 ... CARB.: slide radused, "OEM" stock needle raised 0.050, idle mixture screw out 2 1/2 turns from seat(you will have to remove EPA PLUG), #48 low speed jet, and a #180 high speed jet ... MUFFLER: put a same size hole on the right rear of your muffler as is on the left rear ... It will same you BIG $$$.$$ and run just as good as the after market exhaust stuff ... In BLASTing LaFayette | ||
| Gearheaderiko |
Remember, statements posted here are often the individuals opinion and may not necessarily reflect those of Badweb, The Thumper Forum or its members in general. | ||
| Woody1911a1 |
"Remember, statements posted here are often the individuals opinion and may not necessarily reflect those of Badweb, The Thumper Forum or its members in general." yesssssss remember R80 is just asking what he needs to do when he gets his wifes new blast home and ridable !!! | ||
| Buellistic |
Gearheaderiko: Looks like you have picked up a follower ??? The one's that start out with "REMEMBER" do not want you'll to know anything ... "BUT" it is up to you to separate FACT and "BUELLschitte !!! In BLASTing LaFayette | ||
| Woody1911a1 |
excuse me Buellistic , but i follow no one . if you take offence i'm truley sorry , that was not my intention . between tuners your advice would make for some spirited bantering . as advice to people coming here for help "Remember, statements posted here are often the individuals opinion and may not necessarily reflect those of Badweb, The Thumper Forum or its members in general." | ||
| Buellistic |
Woody1911a1: excuse me. the word is PARROT !!! "i" do not take offence as it is FREE SPEECH ... As for tuners TUNEing, the "BUELLschite" "i" put out is to make your BLAST "LAST LONGER" and "RUN BETTER", not spending the BIG $$$.$$ aftermarket/RACE parts ... In BLASTing LaFayette | ||
| Woody1911a1 |
excuse me , i am NOT a parrot dude !!! what i say , i say on my own !!!!!!!!!!! and i will NOT turn this thread into some personal flame war as you seem to want to , dude ! | ||
| Buellistic |
Woody1911a1: The word is "REMEMBER" ??? In BLASTing LaFayette | ||
| Woody1911a1 |
no the word is :"END" as in end of discussion | ||
| Swampy |
Can'twealljustgetalong????? Also lets not forget to make sure the primary gets adjusted properly, as that will make major improvements for the shifting and general joy of riding the Blast! | ||
| Buellistic |
BLASTers: The rest of the story is to put in a #175 high speed jet ... Nobody has said to check your timing ... Nobody has said to get a Factory Service Manual and Parts Book which tells HOW ... In BLASTing LaFayette | ||
| Gearheaderiko |
Personal attacks will not be permitted and further or previous attacks may be deleted. Buellistic: Do not take offense. The web is a funny place where anybody can say anything and say its fact. If someones reads a post that seems to contradict the majority consensus it is their responsibility to do further research if he wishes to believe the contradictory advice. It is the way we learn and discover alternate views (right or wrong) and new ways of doing things. Otherwise, we are just sheep. | ||
| Ezblast |
Concur! | ||
| Berkshire |
to find the valve lift for non-stock rocker arm ratios, divide the "high lift" ratio by the stock ratio - this gives you the ratio of one rocker arm to the other: 1.75/1.63=1.0736 (lift is increased by 7.36%) in the above example, the high-lift ratio is 1.75:1 (there are others out there) and stock ratio is 1.63:1 (hopefully correct). once you have this number, you just multiply the advertised lift by it: 1.0736*.536"=.575" so the SE "536" cam would give you .575" lift with 1.75:1 rockers. ------------------------------- there is a common misconception that high-ratio rockers change the valve open/close timing. this is not true, but there is a good reason for people to be confused. how can high-ratio rockers increase the valve lift without increasing the duration? they do it by opening the valves faster. the slope of the cam lobes is very gradual right at the transition between where the valve is closed and where it just starts to open or just finishes closing. the transition is so gradual, it's hard to tell exactly where this happens - that's why they measure duration at .053" since the high-ratio rockers open the valve faster, the valve will get to the place where it would be open .053" a little sooner than with the stock rockers, and the original place with .053" lift would now be getting: 1.0736*.053"=.057" so yes, the ".053 duration" does increase, but you have to remember that 053 is just an arbitrary number that's thrown in to make measuring easier. the real duration of the cam stays the same - the difference is that the opening & closing rates are faster, aka "more aggressive". this means that the "valvetrain dynamics" are not as gentle as before, so it will take higher spring pressure at full lift to avoid valve float, and higher seat pressure to avoid bouncing the valve off the seat when it closes... and of course at full lift it will also be .034" (.575"-.536"; the additional lift) closer to coil bind and retainer/guide interference. when springs soften up, it doesn't change the maximum lift you can have before coil bind - it changes the maximum rpm at which the spring will be able to keep the valvetrain tight. example: i have some very soft "utility grade" springs i use for clearance checking. because the spring wire is so thin, they won't coil bind - in theory, you could say they're good for 1" of lift! but they're probably not even strong enough to keep the valvetrain together at idle. IMO, it is VERY misleading when spring manufacturers say that a certain spring setup is good for .XXX" lift... oh yeah? with what cam and at what rpm and what valvetrain? it all matters! just my $0.02 | ||
| Berkshire |
my other opinion is: it's generally risky to use old OEM springs for anything more demanding than a stock cam with stock rocker ratio and stock rev-limiter. when the cam pushes the valvetrain, the springs are what it is pushing against. the harder the pushing, the faster things wear, and the more likely something will break. manufacturers don't like things to wear out or break, so they use gentle cam profiles, which can be countered with soft valve springs. ideally, they would use the softest possible springs that will get the job done, so any cam, rocker, or rev-limit change would be too much for the springs. the Blast was tested very thoroughly before production, and it seems likely that the "factory approved" B50 cam upgrade was also well tested, so the stock springs should be good for the B50 cam -->with the stock rocker arm ratio and rev limit<-- compared to stock rockers with a B50, high-ratio rockers with the stock cam yield more lift, and also increased open/close rates, so that combo would require better springs... and then you'd still be stuck with the stock duration. -------------------------------------- I bet the "gentle" SE cams would be ideal candidates for high-ratio rockers! (with appropriate springs, of course) | ||
| Berkshire |
more "deep thoughts"... while riding, primary chain tension is controlled by the throttle... Twist back, and the top of the chain gets tight. roll off quickly, and the bottom of the chain gets tight. it looks like the springy shoe just holds the slack bottom half of the chain upward during WOT. (to feed onto the clutch sprocket better?) at high rpm/low throttle, the slack is at the top, so why isn't there a spring-loaded shoe up there? (gravity does the job?) the bottom of the chain would be pulled tight then, pushing the springy shoe down. if the shoe hits the stop before the chain is stretched to a straight line, then the chain will rub hard on the shoe. ...so the ideal shoe stop adjustment* would be where the tip of the stop is -->just<-- at the point of contact with the bottom of the shoe when the chain is pulled tight to simulate "engine braking" conditions. setting it that way would require the Blast cover to have inspection holes in the XB location (to put tension on the upper chain) and near the top of the stop (to gauge stop/shoe clearance). * this is my "alternative view"; not factory endorsed. (Message edited by berkshire on December 09, 2006) | ||
| Ezblast |
Ralph concurs, and I find this very informative and well thought out - thank you! GT - JBOTDS! EZ | ||
| Blake |
There is a "stop" on the primary chain adjuster/tensioner shoe? | ||
| Blake |
I trust what Buellistic says is pretty darn good advice. He does like to run a bit on the fat side though.  |
