A loud pop, then engine dies, then I have to push a cb350 2 miles

Helicoil versus tap and die for stripped threads in an engine

Hey guys.
Alright, I picked up a tap and die set. The guy at the store recommended this over the helicoil....it was just before closing so I decided to buy it and if the consensus is a helicoil is better ill just return it.

Now, with a tap and die, ill be increasing the size of the thread...from 6m to 7 or 8m where as with a helicoil I'm essentially installing a new 6m thread after drilling out the old one.

Any thoughts guys?

I appreciate the help on this....kinda entering new territory for myself.
 
Great candidate for a helicoil. No worries, it happens.
 
The "rubber things" are valve seals dont let anybody tell you different they press on the valve guides under the springs and you need them.
 
bradj said:
The "rubber things" are valve seals dont let anybody tell you different they press on the valve guides under the springs and you need them.
Click to expand...

I believe you and ill put tem in tomorrow.... bu tthe military officer inside me demands i ask your references....do you know where that comes from. I just have never head of it or seen it in the manuals.

Is this a modern add on? Or something that's always been done but escaped clymers and the Honda books

I'm rolling a 71' cb350 K3 (in case that matters)

I appreciate the input, brad.

Have a good night.
 
They keep you motor from smoking due to oil running down the worn 40 year old exh guides. i worked in a machine shop for years and have built thousands of automotive and motorcycle cylinder heads nothing makes your special. honda may not of put them on from the factory idont know. but i do know my 50 chevy truck didnt come with seat belts.
 
It has been a decade or three since I owned a CB350 and I still can't shake that memory. It still haunts me. :)

Anyway, what I can't remember is whether it had oil seals on the valve guides. The fact that someone thinks not suggests that perhaps they were added as a model year upgrade over the years. We know that CB72/77 did not use valve guide seals. Cb160 also missed them, but they did come in on the 175 and Cb200 had modern type guides and seals.

That suggests to me that some CB350s probably had seals. Check the manual and parts lists to see when they were introduced. Another way to tell is to look at the guides in your cylinder heard. Are they machined to take seals or not?

http://dicky-pickles.org/d/motorcycles/definitive-word-cb350-gasket-kits suggests that the CB350 never had seals. I onl;y have a K2 parts list and it does not have seals, but I don't have a K4 list to check.

I did check BikeBandit and they also do not list seals for the last 350 twin. Check the guides.
 
Outobie on the hondatwins forum builds race 350s and has said that sometimes he has used them and sometimes he hasn't, and that the valves don't get a whole lot of oil on this bike anyway, so there is very little loss without the seals.
 
Ill throw them on.... I'm always about saving myself time later. Thanks Brad. And the rest for the extra input.
 
The real question is whether the guides on your motor are machined to take oil seals. If they are, fit the seals. If not they won't stay in place so don't fit them.
 
Alright, they are on.... But the entire time I was struggling to get the valve keys back in I was swearing your name brad....just kidding

Teazer, those valve seals fit snug as a bug. It was evident the way they fit, almost clicked, into place they were meant to fit in the k3 engine.

Alright on to autozone for the helicoil
 
If it isn't too late, you can get helicoil knockoffs at NAPA for less. Once you have the tool, the helicoils themselves you can buy at Harbor Freight on the super cheap.
 
Rich Ard said:
If it isn't too late, you can get helicoil knockoffs at NAPA for less. Once you have the tool, the helicoils themselves you can buy at Harbor Freight on the super cheap.
Click to expand...


Helicoil is installed and its holding strong. I got the "Fix a Thread" at AutoZone and the part broke during installation....long story, but the threads are good and holding.

I just got to putting together the cam shaft etc when I noticed two of my rocker arms are way out of spec, some damage I didn't notice during the break down. I'll put up some pictures for shits and giggles.

So now I'll have to find at least 2 new ones. Anyone have a spare set or know a place to get them where I don't need to drop $160+

One step forward, two steps back.
 
Rich Ard said:
Would have been three steps back if you hadn't noticed :D
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Well put. I just need to keep things in perspective

I found a graveyard of 350s in St. Louis .... I got one new and one "previously loved" rocker arm for $50 ....that's a hell of a deal. Plus now I know where to go when I need one of three parts I haven't replaced on the bike.

Ill wrap this baby up this weekend

Take care boys,
 
Problem with Valve positioning

Hey boys,
I wish this was just a simple timing question, but, I'm afraid not. When I got ready to install the side covers for the Cam shaft, the right Exhaust port never has a gap and never has any play in it. It's also notable that the side covers do not go on easily, I really have to manipulate them before they go on. That is to say I have to cycle the shaft through the rotating the stator to make it fit....its really a bitch...which leads me to concern.

Before I put the side covers on there is play in the rocker arm, and I cycled all parts (pins and arms) to ensure its not a defective part.

To be sure, I have everything built up correctly, correct torq specs on everything, cam sprocket "L" inline with with the alternator "LT". Cam spoke properly alligned with the "Mickey Mouse ears up." I redid everything to make sure I didn't fuck up something simple.

Again, this isn't my area of expertise, but I have a few guesses: (1) bent cam shaft...I don't know if thats even possible, and frankly, its hard to tell by looking at it. But thats one guess (2) I've noticed a significant groove in the top of the right side case, actually now that I just checked it, it's on the left side too ...perhaps the cam shaft is getting pigeon holed in there and keeping the rocker arm tight? That seems doubtful.

Just as a reminder to anyone who is new to this post. about 3 weeks ago I sheered the two bolts holding the cam shaft to the cam sprocket. This did some damage to the rocker-arms and to the cam-tensioner wheel.

I did some looking and didn't see any other posts that really met this description. I'm open to any ideas.

As always, thanks warriors.

-cFogs out
 
You said you bought two rocker arms. I don't want to rain on your parade, but there are two different rocker arms for the CB350. One set goes with the "Fat Cam" and the other set goes with the Skinny Cam. they are not interchangeable. I have read where the symptoms of missmatching the rockers causes the rocker to not have enough clearance to the valve stem. If your exhaust port never has any clearence then that is probably your issue............. :'( http://www.dotheton.com/forum/index.php?topic=32697.msg351973#msg351973
 
there are early and later heads, the cam and rocker arms don't work together, but it could also be a simpler issue, if I remember right, the rocker installation instructions include a mark on the outside of the arm (the threaded part) that needs to be pointing to the outside of the engine, not toward the cam. I think if that gets backwards you may have the problem you're describing
 
GLENNWOOD55CAMEO said:
You said you bought two rocker arms. I don't want to rain on your parade, but there are two different rocker arms for the CB350. One set goes with the "Fat Cam" and the other set goes with the Skinny Cam. they are not interchangeable. I have read where the symptoms of missmatching the rockers causes the rocker to not have enough clearance to the valve stem. If your exhaust port never has any clearence then that is probably your issue............. :'( http://www.dotheton.com/forum/index.php?topic=32697.msg351973#msg351973
Click to expand...


You wise sages,
It is infact a single "fat" rocker arm. I had never even heard of this, and it makes me feel better. After an inspection of all 4 of my rocker arms, 3 are good, one is bad....to be honest, I even looked them over, but not closely enough.

The good news is, this Rocker Arm was of the ones I picked up from the junk yard, and it was the one that came new in a box. This means that there should be 3 good arms left in that engine.

I'll swing by today and pick it up.
 
Thanks Roc City, I checked the indicators during my initial tests and they all looked alright. That's important to note though, and a mistake I've made many times before. Even if you have every lined up perfectly that's going to make it A LOT harder to get on the side notes.

Glenwood, again, thanks for the rocker arm catch. When I went into the salvage store, they didn't believe and went straight to the manual. Apparently the modern parts manual doesn't note a difference. But I showed them the thread you sent and were convinced.

Next, I helped them tare open a a 1971 CL350...this bike was seized up...looked at the odometer, it only had 9,000 miles on. Any way, after using a grinder, 3 hammers, impact wrench, 2 screw drivers, we were able to break free a rocker arm, and it had virtually no-wear on it. A little surface rust, but that was it.

I put it in and it fit perfectly. I took it back out and put it in some CLR, I'll take a wire brush to it and clean it up a little more as well..

Thanks for the input guys.

Oh & here is a picture of the place I went to (Archway International Motorcycle Salvage), it's in an old 1902 three story dance hall in St. Louis. This is just one quarter of one floor....In case you were wondering what happened to your old bike

http://archwayintl.com/e-store/index.php
 

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