Topic: Changing valve cover, easiest way? HELP!

[Gordon]

Need?  Who said anything about NEEDS!?

It's the things that I WANT that make life worth living!

_{and what I want is to get my old 400F back...}

[Stevearino]

I will trade a little power for a whole lot of convenience.  I was stunned to find that the 550 engine could be dissassemble while in the frame.  Why didnt they do that with the design of the 750?

I still removed the 550 for a complete rebuild, and yes it is heavy.  Almost needed help getting it onto the bench.

Dont cut the frame.  If you want a chopper, buy one, but dont destroy an original.  Yes you can weld it back, but it is still chopped.

If you want power, get a GL.

[Gordon]

I will trade a little power for a whole lot of convenience.

I'm not knocking the 550, by any means, but have you ever ridden a 750 (in good condition)? 
The power difference is anything but "little"!  And besides, how often do you really need to get into the top end? If you do the job right the first time, you don't need to do it again for at least a decade.

[Stevearino]

Touche!

Yes.  I had a '74 back in the day that I put about 30k on.  Ran like a champ.  Still regret giving it up.

My point was more about chopping an original.  And no, I did not puss out by working on the 550 in the frame.

Ever ride a well tuned GL 1100?

[TwoTired]

So, I guess they never welded them back in. Is everyone here assuming that once removed for easy access that a few simple welds wouldn't be used?

I don't know, I see some pretty strange assumptions.

I guess we had better incarcerate all the amen frame builders and stretchers, because we know after they cut a frame wide open, they never weld if back together before riding...

Yeah, a lot of sanity in this thread.

Cutting and welding on frames is good way to introduce twist in the frame as metal expands and contracts with heat/cold.  I think "simple" welds at four points on a frame, not in a frame straightening jig, is just asking for a simply twisted frame.  As was previously stated, if all you want to do is go straight ahead, go ahead and twist or hack your frame all you want. 

Odd, I never noticed any Amen frames on a road track or any of the "stretchers" either.  I don't recall any racer preferring them to say a Rickman chassis, for example.  However, if any frame modifier knew what they were doing, they would do the welding in a frame jig anyway.

Personally I think it takes the idea of "simple" to a whole new level when you have to build a frame jig to complete the task properly.

But, of course, that is much more sane to do while changing your 750 valve cover, than to yank the whole motor and fix it.   Or so, some might think...

Oogely, oogely, oogely -  Credit: Bill Cosby

Cheers,

[Gordon]

Ever ride a well tuned GL 1100?

Not yet, but I've had my eye on the '75 GL1000 for a while now!  <Insert drooling icon>

[Gordon]

Doc,
Let me see if I can explain this a little better. 

Neither cutting and re-welding the frame, or pulling and re-installing the engine is worth it just to put on a nicer looking valve cover.  I'm not advocating either method for this desired result, and from what I've read, the other folks arguing against cutting the frame for this purpose are saying basically the same thing.   

It's become pretty obvious from your posts up to this point that you're really only here to pick a fight, but I sincerely hope that I'm proved wrong. 

[Noel]

It's become pretty obvious from your posts up to this point that you're really only here to pick a fight...

Ya think?

[TwoTired]

I don't recall the poster mentioning he was going racing down a track with it, do you? Yeah, I guess not. Let's face it he said he doesn't even have a garage and he wants to put on a pretty chrome cover.

If he comes here poor boy welding will do it for him for 20 bucks cash.

I didn't hear him ask to screw up the handling of his bike either.  But, you are willing to fleece him of $20 to butcher his bike for him.  How magnanimous! 
I don't really care, actually.  If he wants to follow your advice, I figure he gets what he deserves.
And, I've got all the CB750's I'm likely to acquire, with un-butchered frames, thank-you-very-much.  They'll never see the track.  But, if I have to do a collision avoidance manuever or take a high G turn, I expect they will go where I point them and not make decisions on their own with every bump in the road.

Anyway, the information is out there now.  It's all I can do.  People will have to make their own decisions.  Lots of people hack their bikes.  If they want to pay you to do it, fine with me.  It won't be a bike I'll ever ride, let alone trust my life and limb on.

Happy Hacking! 

[Jerry Rxman Griffin aka MuthaF'er]

OK guys - everyone be nice! He asked what the easiest way to install a valve cover is. 2 ways period. If you do not want to remove the engine then the only other option that I know is to go through the frame. WHICH IS EASIER?? He needs to be able to make an imformed decision for himself and he has had the information for both options presented.  Now I know by now he has also picked up on the safety issue and there is no doubt that this potential issue exists. Just glad we could be of assistance.   

[Terry in Australia]

When you're a newbie with little mechanical knowledge, you generally make assumptions based on first impressions, not experience. The regular posters here who have some years of experience under their collective belts have a responsibility to provide information on how to perform these functions in the safest possible manner.

There was never a safe second option here, if you want to remove and replace your cam cover, you'll need to take the engine out. If you don't want to remove your engine for top end work, buy another bike. I'd ask though, that if you don't know what you are talking about, don't argue that dangerous modifications are an acceptable option, that is just irresponsible, and not in the spirit of this forum. Cheers, Terry.

[nteek754]

YES YES YES  I agree with Tery and all that say  NO! DO NOT CUT ANYTHING  now  I do have in my collection  one 1970 (frame) with a 78 750 engine mounted when I got the frame it had I think the 70 engine or should I say the bottom of the engine on the frame  I first thought  who would take engine off remove head and jugs and put engine back on  hmmmm well  after striping the bike and intalling the  78 power plant  and re painting the coffin tank and sidecovers  nice bright yellow my  plate says YLW JKT  buffing the  8 inch over front end  and makeing a pretty sweet chopper  I realized in all this they had actually cut those frame rails  now this is one of four seven fifftys I own  and I would never do this but in all fairness the old chopper goes down the road really nice and yup I do not drive it like I do any of the others like my baby 1973 K3 with an 636 kit in it  sadly its at the shop having some wiring done so only rode it once with the new  heartbeat cant wait to twist it up good luck with your gasket seven fifty four ever

[78 k550]

Gordon,
 You eyeballing my new to me 75 GL1000.    I should have it on the road next weekend. Where you looking at this GL1000. I wish mine didn't have a leaky water pump.

Paul

[eldar]

please stop acting like the victim doc. No matter how good a weld is, it is still not as good as an unbroken piece. Simple as that. Also without a frame jig, there is no way to be sure that the frame is still straight after the weld is done. ALL bike makers worth ANYTHING know this. Honda did not just lay the metal on its side and weld it hoping it would be straight, even harley does not do that.

I can very well understand that whacking the frame is much easier than dumping the engine. But if you are going to replace the cover, why not do some other work such as replacing the cam chain and such. IT is easier to do that with the engine out.

So do you
A: whack the frame and risk having it not be straight and weaken it, just to put on a valve cover  OR

B: pull the engine and do a bunch of work thus greatly extending the period of time before you have to pull it again.

You want to cut and weld, thats fine with me. it is your bike. I however do not recommend it unless you have a frame jig and reinforce the spot that is cut out.

You dont like that answer cause it does not match what you think? too bad so sad, get over it.
Just as you can have your opinion, everyone else can have theirs as well.

[eldar]

And none of your methods can absolutely gaurantee the frame is straight. and none of those methods can ensure the frame is straight WHILE you are welding it. SO again you are in the wrong. thank you very much. You talk alot but really say nothing.

Also a weld is a patch, nothing more. You cut a piece of metal apart and weld it and unless that welds is reinforced, it will be weaker, on top of that, the application of heat required to melt the metal to weld it will make the surrounding metal weaker also. Please stop boring us buddy ok.

[cben750f0]

now b4 i get hammered aswell, i am a fitter and machinist by trade, have been for nearly 15 years, have been welding for a fair bit of that time, and i am only goin on what i have been told, i agree that cutting the frame is quicker, and pullin the motor is PITA, but i worked with a bloke who built truck trailers, and he made the point of sayin that, you shouldnt weld across torsional lines , eg across the line of stress... i dont have my CB here but, wouldnt welding across the tubes, particlualy in the region above the the vlve cover(those tubes are quite long), be considered to be across one of these stressed areas?.

   i am not entirely sure, this is why i am asking, and i am not a fame builder, also what steel would these frames be made of?, chrome moly?, cold drawn tube?, mild steel?, all of these materials will granulate if exposed to too much heat, and eventually crack, now b4 you get stuck into me about judjing your skills, i am not, i dont know you, but i s'pose i am just trying to point out, that if and i mean IF, you have any reservations about it, better left alone than, to have something go wrong while enjoying a great sunny day,

   and yes i am affraid to do that sorta stuff, because i DONT know the net affect of me messin with the frame, the bikes weight around 250kg's, i would rather take the time and take the motor out, than worry if , and again in mean IF, the work i had done was gonin to affect the bike in any way, take the motor out, you have no worry, cut the rails, you may have no worry, but ..... and thats the problem, the ....BUT.

       ultimately in the end, you will do what you want to do, and thats what its all about, i agree with you on some of the points, and yes i have read the hole thread, and i can agree with what the other guys are sayin.... if you do it , post and let us know how it went, you may come up with somethin wecan all use, but in contrast, if it all turns pair shaped, you will proabably find knowone will want to know about it.... .... just be safe man, ....peace

[eldar]

Cant you have to get yours out first. sorry just keeping a wheel from moving is not going to ensure alignment. But of course you cannot ever admit you are wrong. You certainly have some insecurities. So please when you correct someone, make sure you are actually right instead of bull-headed and wrong. Sortry but tt and the others have YEARS on you and you still try to argue with them. Please buddy maybe you should read up some more.

I am sure honda and anyone else who know how to weld is aware of metal fatigue from too much heat, obviously you are not but that is not my problem. They take pains to make sure everything is welded correctly, straight, and has the required strength.

So when you can stop being wrong, let us know. Hope your foot dont taste too bad and I hope mine does not hurt your can too much. Done now and still in agreement with the other who DO know what they are talking about.

You should also ask how some of these people ride before throwing around chicken. We are starting suspect you are a new rider. How wide are YOUR chicken strips?

[ofreen]

I must be bored, otherwise I'd stay out of this.  The question 77CB750 asked was what was the easiest way to install the rocker cover.  I've been cutting stuff up and welding it back together for over 30 years.  It is true that a weld can be just as strong as the surrounding material.  It can be stronger using various techniques. But a weld improperly done can be far weaker and look no different than a good weld from the outside.  For the average person, cutting and welding and doing it properly would be a bigger hassle than just pulling the engine.  Pulling the engine out and putting it back in is not that big a deal.  I did it by myself once on the 750.  I had help the last time, and believe me, that is the better way.  (Big tip - remove the exhaust studs)  By the time you are done, you will be a lot more familiar with your motorcycle.  Always a good thing.

[MRieck]

 Boy... I stumbled onto this thread. I personally like a shaking up especially when it comes to opinions. Jigs hold stuff in place after it gets hot. Performance Bikes just had Harris build a GS 1000 frame for vintage Bol d'Or. All tig brazed as not to warp anything. My personal opinion.....I could have went with that cutting stuff but never did AND it would have made my life easier to on several occcasions. As to ruining a frame in regard to "straightness"...I din't think so. There is a lot of material to absorb heat. I'd still just pull the engine.....I've done it myself for Christsakes.

[Terry in Australia]

So, you've actually performed this particular mod on a CB750 have you mate? Or are you just guessing that it'll work? Seems like you've typed a lot of words here, but if you don't actually have any experience with this mod, then you haven't said much to convince us that you know what you're talking about. If you have, post a pic, I'd like to see how you've done it. Cheers, Terry.

[GroovieGhoulie]

How do these same people view necking out a chopper ? I guess they are absolutely horrified and would never ride one. Gee, that's called sawwing and welding, or you AREN'T going to have one!

That's your WHOLE front wheel if that goes!

Yeah, this will happen:

http://www.goingfaster.com/angst/halfharley.htm

DISCLAIMER: I know the site is anti-Harley, (not wanting to start a Harley war) but that one article is the result of some bad welds letting go on BOTH ends of the steering head.  Most likely from a guy who cut and welded his own raked-out chopper.  I doubt a factory Harley, even an AMF model, would let go like that.

[siter81]

Well first off i am a certified fiber optics/system tech for cable.So i am not qualified to speak on welding or modified frames? Anyway i would just pull the motor out the normal pain in the ass way.Yes it is a pain(i have gotton to do this myself twice now in 7 months)but save the other hassle's No other worries except where did i put that darn shoehorn to get that heavy f----ing heavy motor back in the frame.Yes the one i used to get the motor out.


Siter81     

[Noel]

So are we still arguing about whether this fellow should install his chrome valve cover (a purely cosmetic mod) by chopping tubes out of a perfectly good frame?

Seriously? 

[Terry in Australia]

I do like Doc's self-comparison to the Wright brothers, but I'm pretty sure that taking a hacksaw to a perfectly good bike frame doesn't quite compare to the worlds first powered flight, but if I'm wrong and they eventually build a museum to honour half-assed frame mods, (and not just an honorary mention in "The Darwin Awards" when the thing eventually lets go and spits the rider down the road) then of course I will apologise, ha ha! Cheers, Terry.

[Noel]

Careful Terry. That sort of post is likely to get you a deluge of increasingly abusive -- and decreasingly lucid -- PMs.

OTOH, you might enjoy that!