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Old 06-12-2012, 03:09 PM   #16
bernardofeio OP
Bernardo Feio
 
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Hello

Thks for all the answers.
One thing that really catch my attention is the fuel consumption that in my experience is very good.
The flat torque curve is very appealing since I don’t have a very aggressive driving style… and while off roading torque and low revs are always welcome (in my opinion)
One more technical question.
To change the camshaft I “just” need to remove the front end of the engine, remove the push rods and swith the shaft?
Of do I need to remove the engine (or the gearbox) to gain access to the rear engine?

thks
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Old 06-12-2012, 03:44 PM   #17
adventure950
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Quote:
Originally Posted by supershaft View Post
I think I can understand how cam timing might lower the shakes and shudders. I would think it would be mostly flywheel but what works works! Maybe someday I will be able to check a bike out with a cam like that. Time will tell if loading the engine that much at that low of a rpm is hard on the rod big ends.

My riding style is just the opposite of yours. Ice, gravel, wet? I keep my revs high. More steadying engine gyroscopics and better traction control in my opinion.
Hi supershaft maybe your style makes lots more sense - but im a big woose these days, years ago i rode on the edge most of the time, now got too many aches, pains and old injuries to be able whether I want to or not -so slow it is. Bit like a trials ride vs a motocross i suppose - My biking days are now out on the pasture - taking it all very easy.
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Old 06-12-2012, 03:48 PM   #18
Rucksta
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A new cam is a good time to do the cam followers as well.
That would require removal of the barrells.

If you want to risk leaving the followers in place remove the rockers and push rods and stick a telecoping magnetic pick up device down the push rod holes to retract & retain the followers 4 required.
You will also need to addrerss the sproket on the camshaft. Recomendation is ordering a new sproket but if reusing the old one removal from existing cam and replacemnent on the new is required.
Might as well do a cam chain while your in there.

Scope creep it's what projects are made of.
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Old 06-12-2012, 04:28 PM   #19
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Quote:
Originally Posted by adventure950 View Post
Hi supershaft maybe your style makes lots more sense - but im a big woose these days, years ago i rode on the edge most of the time, now got too many aches, pains and old injuries to be able whether I want to or not -so slow it is. Bit like a trials ride vs a motocross i suppose - My biking days are now out on the pasture - taking it all very easy.
I think I am there after my last get off too. But still, after first gear it just depends of what gear you pick, not the speed. Just last week after nine months all my nine broken bones are back together! YEA!! My dislocated little toe is still rubbing on my shoe real bad! I made it to 44 years hard riding since I was six!
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Old 06-12-2012, 06:20 PM   #20
ontic
 
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Thanks for the thread and feedbacks on use,
This is sounding right up my alley for what I am trying to make my G/S- a low to mid range torque beast. The lower it pulls strongly from all the better for me, and like some others I have no need or desire for much over 6,000 rpm.
Each to their own, but I love the feel of the boxer engine thugging along around 3000-ish rpm (give or take 1000 rpm), and I'd much rather have a bike that growls contentedly up and around dirt road at 2.5k rpm than one that starts singing at 6.5k rpm on a bitumen corner. It is all about the style of riding and situations I wish to put myself in. Road racing is not for me (and I don't mean to be argumentative here).

I have the siebenrock 1000cc kit ready to go on, the higher 5th and after just getting back from the alpine rally on my R90 I have suddenly (and finally) gotten the desire for a lower 1st- which I will also buy (I burnt the crap out of my clutch a few times on some dirty stuff and really would have appreciated a much lower gear and/or lower power band).

for a camshaft swap- (trying to determine the likely scope creep)
Along with the standard timing chain kit I have, I've already got both new sprockets for the timing chain (which sorely needs doing anyway).
Engine will be coming out, gearbox off and apart, Jugs will be coming off anyway to swap.
Are the followers a might as well do if you are in there thing- or more of a check and keep them if they are OK kind of thing? Engine is unknown mileage from a roughly treated bike- runs well aside from a very loose timing chain.
Any other stand out items of might as well do while you are that far in?
Cheers,

also,
is motoren israel the only place to get this cam?
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Old 06-12-2012, 11:39 PM   #21
Padmei
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What can go wrong with the followers?
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Old 06-13-2012, 04:47 AM   #22
adventure950
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The cam followers get a bit worn more so if the oil has been allowed to run a bit low at any time - i replaced mine in the rebuild as the originals were very badly scored.
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Old 06-13-2012, 05:54 AM   #23
Rucksta
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Quote:
Originally Posted by Padmei View Post
What can go wrong with the followers?
My info is they wear to match the cam lobe.
The few engine building skills I have are learned from watching someone who knew what he was doing.
He always tracked which pushrod went which way in which hole and which follower rode on each lobe.
Changing the followers with a new cam was a given
Much like new disk new pads
I always learned the hard (expensive) way by not following his advice.
Someone who knows more than I will be along with an explaination soon I hope.
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Old 06-13-2012, 10:25 AM   #24
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When you get a lot of experience with airheads, your opinion might change. New cam or not, my advise is to replace the flaked lifters and reuse the good ones. New lifters might flake. The ones that are in there and haven't yet probably won't.

For instance, At 28,000 miles, My R100 had a lifter get bad enough to chew up the cam. I put a brand new sport cam in. I had two bad lifters so I replaced those two and kept the other two. 70,000 miles later I take it back apart to do a valve job. I lucked out with the two newer lifters and all four were perfect so I put them right back in! The chances of that happening with all four new lifters are slim indeed. I have seen this story fold out numerous times so I think it is a good plan. Of course, the sport cam is still perfect.
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Old 06-13-2012, 01:11 PM   #25
Padmei
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Bugger... so if I mix up the pushrods on one side when I reassemble my motor (50/50 chance) what could happen? i thought a valve adjustment would take care of any difference?
Also by scoring you mean on the bottom of the follower (lifter?) or on the side- or both? Mine seem nice & smooth allround but nice to know the answer.
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Old 06-13-2012, 03:25 PM   #26
supershaft
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The exhaust pushrod is almost always stained darker for running hotter. Which way in can almost always be settled by where the head gasket rub marks are on the pushrods.

I mean the bottom of the lifter. That is where they usually wear.

If you mix up your pushrods, it will most likely effect nothing anyway but I always try to put them back where they came from as a matter of principle.

I don't think I have ever seen a simplex cam sprocket even close to being worn ontic. I have seen quite a few duplex cam sprockets worn way out but . . . .

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Old 06-13-2012, 09:53 PM   #27
supershaft
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Well, those marks are from the head gasket and usually the very end edge of one of the pushrod tubes either in the head or in the cylinder. Yes, our very long pushrods flex THAT much.
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Old 06-14-2012, 02:50 AM   #28
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Good discussion,
thanks,
So,
one vote for new cam - new followers,
one vote for if they are still good then they are good ones so keep em.
I asked because I think I'd heard aspects of both arguments before.
I suppose the way to start is to see what they are like in the first place and then see which direction to take.



Quote:
Originally Posted by supershaft View Post
I don't think I have ever seen a simplex cam sprocket even close to being worn ontic. I have seen quite a few duplex cam sprockets worn way out but . . . .
Oh well, I bought both sprockets so they'll both be going in. The timing chain is really loose and noisy at the moment I was kind of assuming the worst. Not too much money wasted on that if it does prove unnecessary.
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Old 06-14-2012, 11:21 AM   #29
supershaft
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I just thought to ask: How's the pinging situation with those cams? Is it like a R60/5? I forgot about that cam increasing effective CR.

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Old 06-14-2012, 04:02 PM   #30
supershaft
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Quote:
Originally Posted by ontic View Post
Good discussion,
thanks,
So,
one vote for new cam - new followers,
one vote for if they are still good then they are good ones so keep em.
I asked because I think I'd heard aspects of both arguments before.
I suppose the way to start is to see what they are like in the first place and then see which direction to take.





Oh well, I bought both sprockets so they'll both be going in. The timing chain is really loose and noisy at the moment I was kind of assuming the worst. Not too much money wasted on that if it does prove unnecessary.
You'll get a lot more votes on replacing all four lifters since that is about what every hot rod book out there advises doing. I would replace them all in most engines but after working on and rebuilding a lot of airheads, I went my own way on this subject. I am definitely not the only one that has come to the same conclusion.

I have replaced simplex timing chains that were getting into the bearing web, the cover itself, and pretty much anything else that was around for it being looser than a goose but I have still never seen ANY wear on a simplex cam sprocket. Oh well, they aren't that expensive and if you are replacing your cam you have to reset your cam end play anyway.

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