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Hello!
My name is Johan from Sweden. I have a r75/5 - 72 swb.
I have a pair of REALLY bad followers and a camshaft that i need to replace. The followers is the old type (flat) so ill need to change them all. Is it alright to put some good used parts in the bike or should i go for brand new? Will the camshaft and followers "have a problem" with eachother beacause they come from different bikes with different miles etc?

Oh, and heres a picture for your entertainment! :

Best regards
Johan
Sweden

Joper wrote:Hello!
My name is Johan from Sweden. I have a r75/5 - 72 swb.
I have a pair of REALLY bad followers and a camshaft that i need to replace. The followers is the old type (flat) so ill need to change them all. Is it alright to put some good used parts in the bike or should i go for brand new? Will the camshaft and followers "have a problem" with eachother beacause they come from different bikes with different miles etc?

Oh, and heres a picture for your entertainment! :

Best regards
Johan
Sweden

You don't say what the history of the bike is or the mileage. Much depends on this. You do not want to put expensive and long lasting new parts into an engine that only has 50k worth of life left due to wear on other parts. Good used parts are fine, including any you have. You only have to replace what is bad. A decent lifter is a decent lifter---but personally, if a lifter has the tiniest pit, I replace it. Often I only need to replace one. Used won't last as long as new of course and parts that haven't broken in to eachother need to do that---new or used.

The lifter breaks into the pushrods. Check that interface carefully. Good time to update to the newest type pushrod. Also check the lifter bores in the block and make sure that is decent.

You check the oil pump and timing chain/gears while the cam is coming out, and check the cam bearing bores in the block. You also check the crank journals, clutch and clutch plates, etc. Once you have done all this, then you know more about the overall wear on the bottom end and can plot strategy. You know the cam has to come out---all the other checks are right along the way and cost nothing. So get it out and measure up the easy things.

Thanks for a fast answer! I actually dont know the mileage on it, somewere around 50 000 - 80 000 miles probably. The overall condition is good. Shockinlgy it ran quite good! Except for some ticking it sounded good to. I traded it for honda cb750-81 that i had around 1000 dollars in so i did a nice deal anyway! The piston, valves, seats all look very good. No play in the rods. The clutch is almost brand new. Someone has done some work on it but skimped bigtime on the cam and lifters...
Ill check everything while im "there" but i will probably go for used lifters and camshaft then. If i start buying new stuff i will want to change that, and that, and that, and....

Oh, and one more thing.
My followers/lifters is all flat. When i look on ebay i find that they have a "pointy" area were the pushrod meet. Is it a bad idea to use two of my flat old ones and two of this kind:
http://i.ebayimg.com/t/75-BMW-R60-motor ... ~60_57.JPG

Mine look like these:
http://i.ebayimg.com/t/1974-BMW-R90-6-S ... ~60_57.JPG

I dread to open the issue up, but what kind of oil were you running or is this a result of a previous owner (ab)use? For the cam lobes and follower surfaces to be that pitted suggests that a poor quality oil with out enough ZDDP was used. Something to consider going forward.

Kurt in S.A.

Hehe! I have no idea. Ive owned this bike in about a month and only driven it round the block! The strange thing is that the only lobe that is worn is the one on the picture, left side exhaust. The right side exhaust have some marks and the intake lobes look perfect.. Very strange to me!

You may replace the cam with a good used one and the same with the lifters. A good used cam should be cheap, as they seldom fail like that.

I have put together engines with all used parts and none "knew" each other before.

Joper wrote:Hehe! I have no idea. Ive owned this bike in about a month and only driven it round the block! The strange thing is that the only lobe that is worn is the one on the picture, left side exhaust. The right side exhaust have some marks and the intake lobes look perfect.. Very strange to me!

It may have begun with some rust. Look for pitting in the bores or other rust damage.

The exhaust valve is a hot spot and the oil flowing down the exhaust pushrod tube to the lifter is the hottest---the exhaust lifters run the hottest. If the oil was poor/low/too thin you might see problems on those before the others.

You might also have a defect, either in cam hardening or perhaps in the lifter. One surface failed early and chewed up the other.

You could also have a lubrication problem---perhaps a bit of swarf or other defect in the oil way dripping oil on that lobe. Check this.

If the heads were rebuilt the valve spring pressures may have been set up incorrectly. Look for a bunch of shims under the springs. Someone may have set it up for high RPM racing---this has a price.

You want to wonder where all that metal went. Some got around the filter on startup. So you look over the big end bearings. (new bolts there always)if no embedded metal and good spec. no worries on the rest. If you have metal in the bearing and perhaps scoring on the journals, pull the crank and check all bearings. (ug!)

Major lubrication failure will result in discoloration on the crank. You probably would have noticed by now.

You can theorize further after looking at things like the wear on the oil pump---this can also indicate mileage on the motor although looking over the frame and controls can say more, quicker.

The later lifters (spiral hole) are lighter. I would keep all of the same type rather than some light and some heavy ones. That said, I consider the camshaft to be in 'deep'. lotta work to change it (and the new on better have a strait nose---beware of that!). But the lifters are not in 'deep'. You can swap them out in a couple hours for the price of new head and base gaskets. And you are in there every 8 years or so anyway for fresh pushrod tube seals. So you might push it there without worries of big effort and expense to replace them later. I have a nice cam sitting here, and probably some lifters, but I suspect the shipping to Sweden from the USA could be steep. Look into it maybe. Bet Duane has some too and he might even pay you to haul them off.

If you don't have magnetic plugs, now is the time.

Those Hondas are getting valuable and even ratty ones are wanted for cafe projects.

PITAPan wrote: Major lubrication failure

Worst Boxerworks handle ever.

That cam failure isn't wear, it is from a bad job of hardening, or faulty metal in the camshaft. I have seen them wear and it shows as wear with the usual scratches. Those are pits in the surface and due to those chunks of metal being beaten out of the cam.

The same thing happens to the followers often. It is far more common for the surface to fail, and less common to see wear.

Major Softie wrote:

PITAPan wrote: Major lubrication failure

Worst Boxerworks handle ever.

Hmm, looking at it from the same perspective as "major lubrication failure", "major softie" doesn't sound all that much better.

Ken