Camshaft Differences

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MSGT-R

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Okay, the purpose of this thread is to explore what Dan started and compare the different cams for the 4 cylinder Wings.
I've ordered two sets of cams off e-bay and, of course, the original set already in my 81' 1100.

Early wings had not only the mechanical pump, but points ignition. The back ends of both cams have these drives sticking out of the rear of each head. The late cams have neither because of electronic ignition (also on the 1100s) and electric fuel pumps. All cams will physically bolt into all 4 cylinder Wings (if you do some chopping).

bikepics-2176469-full.jpg


The height and thickness of the lobes was the first thing that jumped out at me (besides the 1200 cams being worn). So, I proceeded to rig up a way to measure both sets. My husband is not going to be pleased that I used his table saw, but I needed a metal table to secure my dial indicator base. I'll make sure I don't get his clamps dirty..

The first pic shows a simple set of vee-blocks cut from scrap 2x4, and the dial indicator set on the lobe surface. The second pic is the addition of a degree wheel, which is a protractor taped to a carboard backing so I can see the markings better. The bent wire is my indicator.

bikepics-2176467-full.jpg


bikepics-2176468-full.jpg


So far, I have this:

EARLY WING CAM:
Duration: 170 degrees
Lobe Centers: 112 degrees
IN Lift: .273"
EX Lift: .261"
One side of the lobes have a very steep ramp, with a skinny base circle.

LATE WING CAM (1200):
Duration: 145 degrees
Lobe Centers: 115 degrees
IN Lift: .225"
EX Lift: .227"
Both sides of the lobes are equal, with a fat base circle.

More to come.
 
I'm going to have to either do some math, or install the cams to get an accurate opening/closing value in relation to the crankshaft.

Camshafts run at 1/2 crank rotation. Putting the protractor directly on it skews the figures..

My head is gonna explode. :Awe:
 
im aqlways playing music ...then somebody smarter than me comes along and writes it down ....then i get confused when they tell me im not doing it right :smilie_happy: :smilie_happy: yes this is going to be a great thread ....we need to find out witc set of 1000 cams those are 75-77 or 78-79 there entirly :mrgreen: different
 
Very good thread indeed.
But I would like to see 1100 specs as well.
Unfortunitly,untell it can be done with my stock ignition,and keep my mechanical fuel pump I will stick with my 1100 cams.

When I was racing lawnmowers a few years ago I would send my cams to Don Gienger at G-TEAM and he would weld them up with a nickel alloy and regrind them to a more HIPO friendly spec.
www.g-team.us
Maybe we can get him hooked on 1100s and get him into cam grinding for us. :music:
 
A grind of a stock set of 1000 cams is precisely what I'm after but I don't know yet what I'll end up with. So far I've been able to run the 1200 cams on very little money but that will no doubt change when I want to get the tach working.
 
The 1200 with the old style dial tach like the earlier years (84 only I believe) is driven from an ignition control box so the tach must be electronically driven.
Putting that box and tach in my 1100 is an option.
 
Or a tach from another model of Honda..

The measurements I made are not looking accurate.

Here are the specs from the 1100 Factory Manual to compare with the cams I'm working on:

GL1100 @ 1mm lift
In Open: 5 degrees BTDC
In Closed: 43 degrees ABDC
Ex Open: 45 degrees BBDC
EX Closed: 5 degrees ATDC

That would make for a 10 degree overlap.

Doubling the numbers on my readings had the 1200 cam showing:

In Open: 20 degrees BTDC
In Closed: 76 degrees ABDC
Ex Open: 50 degrees BBDC
Ex Closed: 50 degrees ATDC

It can't be that far out of whack (?)

Does anyone have a Factory GL1200 Manual? The aftermarket manuals won't show these figures.
:help:
 
I think you need to also factor in the rocker arm ratios on the cam lift, and valve open/close timing. The cam lobe timing events are not the same as the valve events. That may be where your discrepancies are.... :headscratch:
 
The valve opening events will happen at the same time the lobe comes around, the amount of lift is affected by rocker ratio.
I'm more familiar with automotive specs and operating rules than with motorcycles.
 
Just a short bump and an update. I've searched a couple of places for valve opening/closing specs to no avail. I guess the 1200 Factory Manual didn't include them like the 1100 did. I'm not going to bother Randall right now since he's irritated about that argument stuff with the "race".

I'm going to ask a friend-of-a-friend that has early wing parts, and see if he has a complete 1200 head. After really looking over the cams, I'm convinced that the rocker arm ratio is different from the three different models.. The bumps on the 1200 cam are just not very big compared to earlier models.
 
MSGT-R":1rub8tg8 said:
The bumps on the 1200 cam are just not very big compared to earlier models.

It's interesting you say this because I saw quite a difference in the profile, granted this is by naked eye.

I have a few shots in my gallery album. Looking at the smaller images side by side it makes the different profiles stand out.
Note the image names for which cam is on the right and left in the photos:
gallery/album.php?album_id=671
 
Yeah, I know that one has a "flat-sided" lobe, but the base circle is larger on the 1200 cam. That makes the rise of the lobe less in comparison.
 
chasrogers":3m2m6aw7 said:
hello all I just got some info that yall would like I would think :clapping: :clapping: :Egyptian: :Egyptian: the 1984 GL1200 cam standards are
intake 0.3mm exhaust 0.3mm
of course these are hydrolic lifters so valve spring free lenghth 17.5mm with a service limit of 16.0mm the hydrolic tappet is 0.3mm thus the settings for the tappets this info came complements of KW Honda Ontario canada also he is emailing me the page so I will upload it to the specs section Chasrogers :hi: :hi: :hi:

So duration can be checked by setting the gap at the low end of the lobes and measure degrees from zero to zero as read on the dial indicator. I'd be very interested in how the 79 cams compare with the 1200 after the correct gap is accounted for.
 
The stuff I keep finding is all over the map! Mega Cycle Cams is taking their readings from the valve. I took my readings from the cam lobe. The big differences, I think, are the addition of the rocker arm ratio. They are also starting their measurements at .040" lift. This can vary in degrees depending on how steep the cam lobe "ramp" is. :Awe: Here's the list so far. I'm still going to have to break down and mount all this stuff to my motor and do the measurements, but not until after Wing Ding.

Goldwing Camshaft Comparisons

E-BAY EARLY WING CAM:
Duration: 170 degrees
Lobe Centers: 112 degrees
IN Lift: .273"
EX Lift: .261"
One side of the lobes have a very steep ramp, with a skinny base circle.
Ignition stinger and fuel pump drive present.
All measurements taken at cam lobe.

E-BAY 1200 WING CAM:
Duration: 145 degrees
Lobe Centers: 115 degrees
IN Lift: .225"
EX Lift: .227"
Both sides of the lobes are equal, with a fat base circle.
No ignition stinger or fuel pump drive present.
All measurements taken at cam lobe.

GL1100 MANUAL SPECS:
Duration: in 228 degrees / ex 230 degrees,
(based upon open/close events)
Lobe Centers: 141 degrees (?)
Lift: (?)
Intake: 5 BTDC, 43 ABDC
Exhaust: 45 BBDC, 5 ATDC
No information where the measurements were taken,
or at how much lift.

Mega Cycle Cam (1978 stock spec)
Duration: in 239 degrees / ex 237 degrees @ .040 lift.
Lobe Centers: 112.5 degrees
Lift: .356, *at the valve
Intake: 7 BTDC, 52 ABDC
Exhaust: 51 BBDC, 6 ATDC

Mega Cycle Cam (perf. spec)
Duration: 271 degrees @ .040 lift.
Lobe Centers: 108.5 degrees
Lift: .425, *at the valve
Intake: 27 BTDC, 64 ABDC
Exhaust: 64 BBDC, 27 ATDC

Open road power increase mid-range & top end.
76-77, Stock pistons okay.
88+, Modified pistons.
New valve springs recommended.
$438.00 on customer cores.

Note: Mega Cycle Cam measurements taken at valve?
 
Lift can vary depending on rockers and valve lash (gap) To do a true comparison I think you would start with the dial indicator at a setting that allows for the suggested gap for the cam. Then measure lift and duration. JMO :whistling:
 
Apples, to apples.. .040" lift at the valve, to match Mega's measurements.
 
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