Sifton solid lifter conversion experience ?

Top End (cylinders and heads)
Post Reply
doc308
Posts: 171
Joined: Mon Apr 07, 2008 8:43 pm
Bikes: 1948 Harley EL
1959 Harley Sportster XLCH
2016 Harley Softail Slim FLS
Location: cohoes, ny

Sifton solid lifter conversion experience ?

#1

Post by doc308 » Mon Jul 06, 2009 2:05 pm

Has anyone had any experience with those solid lifter conversion kits (with the springs, lifter cups and adjustable pushrods) in an earlier panhead engine? In order to use akit like that does one need to install the hydraulid tappets first or could the kit be used with the original solid tappets?



steinauge
Posts: 521
Joined: Tue Feb 03, 2009 10:05 pm
Bikes: 1938U,1949FL,1961FL,1968XL,1979FL ,1958 FL, 1965 BMW,1975 Honda CB750

Re: Sifton solid lifter conversion experience ?

#2

Post by steinauge » Mon Jul 06, 2009 5:23 pm

I dont have any Sifton pushrods handy But I do have here a generic aftermarket aluminum pushrod for an early pan and an original pushrod with the hydraulic unit at the top.The ball end sizes appear the same if that is any help.I also have a set of the solid lifters \pushrodsyou describe but sold under the Colony name.The lower ball end on that one is much larger than the original or the other aftermarket pushrods.HTH

NightShift
Posts: 532
Joined: Tue Apr 21, 2009 4:20 pm
Bikes: Two Schwinns, a Hercules, and a Hiawatha
Location: Underground in Illinois

Re: Sifton solid lifter conversion experience ?

#3

Post by NightShift » Mon Jul 06, 2009 6:51 pm

Dear Doc,

Those slugs and springs and pushrod with adjustor kits are for 1953 and later big twins. Throw away the springs at least, unless you save them for over clutch studs for more grab.
If you have hydraulic tappets in your blocks, you gotta use the rest no matter what.
But throw the springs somewhere else.
And maybe if the pushrods are aluminum, they maybe ain't worth the trouble atall. The slugs are probably loose in the tappets anyway.

steinauge
Posts: 521
Joined: Tue Feb 03, 2009 10:05 pm
Bikes: 1938U,1949FL,1961FL,1968XL,1979FL ,1958 FL, 1965 BMW,1975 Honda CB750

Re: Sifton solid lifter conversion experience ?

#4

Post by steinauge » Mon Jul 06, 2009 6:58 pm

Nightshift,I was thinking he said "early panhead" like hydraulic pushrod? RE loose slugs-they are ALL loose that I ever saw. I have had good results with cylindrical bond loctite if I just had to use those.

doc308
Posts: 171
Joined: Mon Apr 07, 2008 8:43 pm
Bikes: 1948 Harley EL
1959 Harley Sportster XLCH
2016 Harley Softail Slim FLS
Location: cohoes, ny

Re: Sifton solid lifter conversion experience ?

#5

Post by doc308 » Mon Jul 06, 2009 10:19 pm

I was wondering if there was any advantage to those kits vs. oem solid lifters/slid aluminum pushrods. If so, in order to use them in apre-'53 pan, I guess one would have to install the hydraulic tappets for them to fit.

Re: not using the springs---wouldn't the springs be good for maintaining more consistent adjustment through the heat range vs the OEM solid lifter/solid pusrod set-up?

One other q---there has been some issue by some on the forum re: using solid aluminum pushrods with OEM solid lifters--I think do to heat expansion issues. Is there a maufacturer who makes steel solid pushrods vs aluminum?

awander
Posts: 1119
Joined: Fri Sep 21, 2007 3:03 am
Bikes: '52 FL
'64 FLH

Re: Sifton solid lifter conversion experience ?

#6

Post by awander » Mon Jul 06, 2009 10:55 pm

I think the springs might stop things from falling apart if the pushrods got REALLY loose(also, they might not), but as far as actual valvetrain clearance, they will do nothing-if they were stuiff enough to close things up and keep them that way, they would also be stiff enough to push teh valves open.

Just my opinion

Cotten
Posts: 6788
Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

Re: Sifton solid lifter conversion experience ?

#7

Post by Cotten » Tue Jul 07, 2009 2:13 am

The springs only confuse the all-too-subjective feel for adjustment.

They have no benefit whatsoever.

...Cotten

panhead5
Posts: 1
Joined: Thu Oct 11, 2007 2:41 pm

Re: Sifton solid lifter conversion experience ?

#8

Post by panhead5 » Mon Aug 21, 2017 2:06 am

Those springs, when expansion of the head and cylinder occurs, keep the pushrod up against the rocker if only for a brief second like the original oil can pushrods. This keep the oil pressure from dropping when the slight gap happens between the pushrod and rocker arm. I have tried it both ways( with the springs and without) and without the springs, oil pressure drops dramatically. I used S&S steel pushrods and adjusted them with slight drag. Everyone says throw the springs out but I have found that they really do help with oil pressure. The other way to keep oil pressure up is to modify the rocker blocks and arms to keep oil from flowing out the rocker arm. Comments are welcome.

Andygears
Posts: 331
Joined: Tue Feb 05, 2013 12:25 am
Bikes: 1950 panhead, 1999 FLHTCI, 1987 FLHTC custom
Location: Daytona Beach

Re: Sifton solid lifter conversion experience ?

#9

Post by Andygears » Tue Aug 22, 2017 1:16 am

I've generally disliked those "insert kits" finding that too often they sit loose in the lifter body. I think that many times they were the "easy way out" to a poor performing hydraulic unit. Rather than find the offender or replace all the hyd. units, read expense, the kits were cheap and fixed the noise for a while.
The springs keeping up oil pressure vs. no springs is new to me and makes some sense. So in a pre '53 non-hydraulic lifter motor with adj. solid lifters and solid pushrods, the oil pressure loss would be similar when hot? Or in a later motor with that setup? In fact, to extrapolate, any solid lifter motor which makes pushrod noise when hot is loosing oil pressure in relation to the looseness/noise. And the oil pressure loss is measurable from the rocker/pushrod seat?

Interesting
Andygears

Post Reply

Return to “Top End”