First highway run; engine bogs at 60

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Ok, so question about the seals- I’m upset because I ordered the kit from Ebay that would arrive the soonest; none of the “tour max” seal kits were in the states. So I ordered one from poland, (since the kits from the uk were showing almost two weeks longer ship times)and the picture showed a “tour max” label on the card. That is NOT what I received. Anyway, it looks like tbe only two seals in this kit that would be the cam seals are not the same size; one is about twice as wide as the other. Is that correct? I’ve picked up on people using two brass bushings on one side and one on the other when retrofitting advance rods on 80-up engines, so I’m assuming the oil seals are similiar?
 
No, you don't double up on the cam seals. In your pic, is one seal a new one from the kit and the other an old one you removed? The proper cam seals are thin so that thicker seal on the right wouldn't be one. It might be a crank seal. If you look back at your post #95 with the info on the cam seals from MikesXS, you'll see they give an SSD number, 25-40-6. That means the seal has an I.D. of 25mm, an O.D. of 40mm, and is 6mm thick. If you look at the ends of the cam, you'll see they don't stick out of the engine very much. You need a thin seal and it has to be pressed in all the way to the back edge of the points/advance housing in order to get onto the cam stub and seal. Here's a pic that shows the inset seal and how little the cam sealing surface sticks through it .....

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If the fatter seal in your pic is the one you removed, that could explain why it was leaking so bad, it's the wrong seal. It probably couldn't be pushed in deep enough for the seal lip to get on the cam.
 
No, these are pics of the new seals in the kit. These are the only two seals in the kit that have the same dimensions, with the obvious exception of the one being wider. I didnt mean double up seals, I’m not an idiot; I meant I thought maybe the two sides of the cam weren't exactly identical, so maybe one side had a deeper seal than the other. I assumed a seal kit would give me two cam seals. Apparently not. Fucking bunk seal kit.
 
Looking at some of the 7 piece seal kits, I see they don't contain cam seals, just all the other engine oil seals. If you have a Yamaha dealer near by, you can still buy cam seals from them.
 
I don't know. The MikesXS kit contains 10 seals, maybe yours is missing one? Did the eBay listing say how many seals were in that kit? I know I've seen some 650 parts from Poland but I can't find that seal kit listing.
 
Everything was in polish. It didnt specify how many or I didnt read it well enough. Either way, it’s not tour max, or what I need, and I’m not fucking with an ebay return to poland. Guess I’m still in the market for cam seals. :wtf:
 
I removed the old manifolds and gaskets today and installed the new manifolds and gaskets from mikes in preparation for my freshly rebuilt carbs. The (I’m assuming to be original) manifold gaskets popped right off, and they are hard, almost like plastic, and a LOT thicker than the fiber ones that came with the new manifolds. They’re around 3 mm thick (just eyeballing) I cleaned both the gaskets and the manifolds in hot water and dawn dish soap. They don’t appear to be deteriorated or cracked anywhere. Am I right to assume that these are better than the “new” parts I just installed? Or is the gaskets being very hard a sign that they are old and maybe not doing a good job sealing? I’m keeping them, and will re-install them if/when the new ones give me any trouble.
 
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ALRIGHT!!! GREAT NEWS
IT WAS THE CARBS
Got the beautiful carbs back from Rick at oldskoolcarbs today. I have to give him praise again, and in case anyone is unaware of him or his services, for christ’s sake check him out. He polishes your carbs to better than new, and I got mine back just a day on a week after I sent them out to him. He sent me pics and updates of his progress, and he maiked me back the shipping envelope for the JBM diaphragms he installed for me as well. Nicest guy in the world to talk to, as well.
Anyway, after an hour or two to carefully reinstall the airboxes and all the rubber seals for everything, and to route the fuel line, I Adjusted the idle screw a bit, and took her down the interstate. She did 85 easy!! Feels so good to have her at full power and looking so sweet with this new seat and shiny carbs. This is gonna be a great week!!!
:bike::bike::bike: Later this week I’ll do a compression test and check/set the valves if needed, and take some more really nice pics to share with everyone a better appreciation of this gorgeous bikes’ overall condition. I decided not to change any of that stuff before reinstalling the carbs so I could pinpoint the problem/solution through process of elimination. Still waiting for my pamco, which is fine because the seal kit I bought apparently doesnt include the cam seals, which are the whole reason I was shopping for seals to begin with. Once I receive the pamco and buy a couple seals though, I’ll have a completely new Pamco ignition setup to replace and improve the original 41 year old points ignition system BEFORE it starts giving me any trouble.
 
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Everything was in polish. It didnt specify how many or I didnt read it well enough. Either way, it’s not tour max, or what I need, and I’m not fucking with an ebay return to poland. Guess I’m still in the market for cam seals. :wtf:
Be sure to check out MikesXS for cam seals. Seal dimensions are shown on the surface facing you. This dimensions are usually opposite the spring side of the seal. There are two different thickness for the cam seals. The narrow seal is SSD number, 25-40-6 is for the earlier models (before TCI) The reason for this is the locating pin for the contact point cam rotor and the advance mechanism on the opposite side. The thinner will ensure proper sealing and not interfere with the locating pin. Here is the link for MikesXS early model cam seals. https://www.mikesxs.net/camshaft-seals-pk-2-sdd-25-40-6.html
 
I appreciate the input. I will have to look at the seals when I get home to make sure, but I think the kit has 1 seal with those dimensions, and one wider for maybe the later bikes. I called my local yamaha powersports store and ordered two seals this morning. Whoever I spoke with on the phone said they didnt have dimensions, but they orderes two “cam seals”. Guess I’ll see in a few days exactly what they ordered.
 
They might be the 7's. That might be all that Yamaha sells now. The old part #, for the 6mm wide seal, has been superseded with a new part #, and the cross-reference for it says it's used on all models.
 
So are you saying I need a 6mm seal and they may not be available anymore, and that yamaha has incorrectly superceded them with a 7mm part that will not work for me?
 
I think the 7's will work as long as you seat them deep enough into the housings. The locating pins in the advance rod, along with the parts that mount on them (points cam, advance disc) aren't the issue as far as clearances go. It's the locating pin in the cam on the advance side, for the advance unit. That one is set in a lot farther. When the housings are off, make sure you clean the ends of the cam where the seal lips ride really well. Buff them clean and shiny with a Scotchbrite pad. This will give the new seals a clean, fresh surface to seal against. One of the reasons these seals start leaking is that the end of the cam that sticks out past the seal gets all rusty. Then that rust starts working it's way into the seal and causes it to start leaking.
 
Gotcha. Thanks for the tips. I picked up some scotch brite pads last week just for this job. I should have just called the powersports store to begin with for these seals. I guess it’s of no consequence since the bike runs fine right now and I don’t have my pamco yet anyway. 5Twins, any input on my post about my original intakes and intake gaskets? I trust your judgement and was imagining you would tell me to keep them and put them back on.
 
As long as they're sealing, I guess they'll be OK, but if you compare them to the originals, you see the originals are much thicker. There may be more going on here than just sealing. That original really thick gasket may also be insulating the manifold from engine heat. I use thick ones, either originals or the ones from the Athena gasket kit (they're thick too). I see Mike's sells them separately and they do look like thick ones, but I never bought any individually so can't say for sure. I managed to find some N.O.S. ones on eBay for a good price. I get most of my gaskets from eBay. You can find originals for usually less than Yamaha or Mike's charges. My latest score was gaskets for the right engine (clutch) cover, $10 each. Yamaha wants about $18, Mike's about $13.
 
I used gasket shellac between the gasket and the new mikes manifolds, and then coated the gasket with a bit of motor oil with my finger before installing it to the engine, so the gaskets don’t stick to the engine.
 
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Okay, first of all, since my issue isnt the engine bogging down, should I stop posting in this thread? Both the issues I’m about to bring up are relevant to earlier posts in this thread I think. So, here they are- I picked up the two cam seals from my local yamaha place. They had one in stock, and ordered one. They arent identical, but the dimensions are the same. They are 25-40-5, not 25-40-6. I read in the cam seal thread about how the XS1 used this size seal. Will these work on my ‘77? Are they perhaps better? 2nd issue; about an hour ago on a short ride before sunset, the speedo I Bought from Jim crapped out on me. It’s been working flawlessly since I installed it, but on this ride I noticed the face vibrating a little, and the needle got just a little Jumpy, which it has never done. The right screw that held the face in vibrated out, and about 15 minutes later the left screw followed suit, and the face vibrated completely around so that the pin that holds the needle is now on top of it, preventing it from moving up. I’m worried that riding with that resistance on the needle may have damaged the speedo. I read a thread about removing/replacing the speedo glass, I’ll have to re-read it. Jim, you have any more speedos like the one you sold Me?
 
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Those seals will work. Just make sure they're flush to the inside of the motor.
Sorry 'bout the speedo... that's the problem with 40yr. old parts.... they're 40 years old. Yeah, pretty sure I got another. I'll check tomorrow.
 
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