82 DOHC 750 tachometer seal

[masiste]

Going to replace the tachometer seal. Leaks.

Anything special I should know about before doing the work ?

Looks like previous owner has a lot of gunk applied to cover around cable.

Will clean around, pull cable and hope the new seal will take care of leak.

[LukeM]

Moving this thread to a better location.
Luke M

[masiste]

Waiting for parts.

Ordered hearth shaped seal for camshaft holder tachometer drive , and round seal for cable to drive section.

Do not want to use bike more than a ride around the neighborhood so I do not get oil dripping.

Anyone used or knows if the bike would leak bad if no cable is attached ?  Thought about getting cable detached, but common sense tells me it would be an open avenue for oil to gash out.

Would that mean no way to get rid of the tachometer ? ( in case of switching to electronic - coil connected tach)

[TOOLS1]

Cycle-X has a tachometer plug.
TOOLS

[masiste]

 Hi.

     Nice link. In case of finding an electrical tachometer ( hooking up to coils like automobiles and newer bikes do ) , this plug would end oil leak issues.

    Only thing is I do not know if it is meant for the DOHC 750 or the SOHC.

    Will write to them to find out.

[masiste]

Today I ordered a plug, on e bay.

Called the guys at Cycle X, but the guy over the phone told me to call tomorrow.

Well. his loss, went to e bay and got a cool anodized in black ( my engine is black )  plug.

My cable is bad, and in order to stop that leak, will use the plug.

Working on my gauge cluster now, so I will not need the cable right away, ( ordered wrong one, it was a. CBX which is not same as rest of DOHC 79-83. Already contacted seller, will return cable aupon delivery, andg et a re fund )

Also exploring the posibility of using an electronic analog tach. The electronic tach, like automobile ones, hooks to the coil, cleaner connection. Analog of course, I like analog gauges, I can see the rpm as it fluctuates. ( try following fast changing numbers ona. digital tach....crazy ! )

This is the plug.

[TOOLS1]

"Called the guys at Cycle X, but the guy over the phone told me to call tomorrow."
Well it was Martin Luther King Day today. I'm surprised someone even answered the phone. The Cycle-X guys have always been very helpful when I have called them, and they are my first stop for parts.
TOOLS

[masiste]

 My bad.

I did not know about Martin Luther King Holiday.

Something was weird about yesterday, that seems to explain. Called DMV and nobody answered.

Fewer than ussual phone calls.......

Sorry Cycle X. Must have been the "X" factor......

Will give it a try next time.

Good thing though, as I remember, Cycle X's plug was offered only in polished aluminum, since my engine is black, I was looking for anodized black. So perhaps Cycle X would not had made the sale anyways.

Cycle X, I'll be back !

[masiste]

 Well

   These plugs will not work on DOHC Hondas ( 79-83 )

   All they show is SOHC photos

   Do not buy.

   That is why I was suspicious

   Called Joker Motorcycles, seller of plug and left a message  , it is Saturday. Thing is, these plugs have a mushroom head, that is wider than body lof plug.

   Plug has to sit down all the way until head rim sits on rim of tach drive port. Joker plug  ( and seems Cycle X also has same shape ) can not sit down all the way, and issue is cable bolt can not go inside into place, to secure plug, because the groove on plug is not in the proper position, it can not reach it, because of plug not going down enough.

   The driver on the DOHC bikes is seated tilted forward, so the rim of the driver has no room on the lower side, for the larger than body head of the plug to go down on port.

   Don't you hate this ? Awaiting for a part for days, then taking the time to install, only to find out it is not the right part.

    NOw, return, and wait for refund.

   But all sites, ( Cycle X, Joker, etc ) say the part fits Hondas CB 750  70s till 83.

   I thought not, cause all photos they show are SOHC, called twice, being re assured it was the right part.

[masiste]

 NOw I got stuck. Tried re installing cable with new seal. Took old seal off bottom of cable.  Now cable does sit all the way down, so adjusting bolt can not go through.

 How do I get seal out from that driver port ?  It is not only difficult to look in there, but how do I get seal out ? ( old seal was stuck to bottom of cable, came out with cable )

[masiste]

LOL

 This seems to be a monologue.  Where is everybody ?

 Got seal off with screw. Verified nothing else was inside port ( nothing indeed) and re installed seal.

  Cable went in amd finally able to insert securing bolt.

  About tachometer plug, beware. as photos on different sites show, it fits only SOHC HONDAS.

  That fact (photos) was suspecious enough to me. Called the seller on e bay. He said yes, indeed, part worked on DOHC HONDAS. He claimed 76-83 Hondas. I told him that 79-83 models are different than earlier ones.

   He insisted. His motorcycle application chart shows CB900F 79-83. He told me my bike, CB 750 F was covered.

   Received plug, so no seal. Called again. Guy insists no seal is needed.  No O ring, nothing. OK.

   Called manufacturer, Joker Motorcycle Parts, them too said it works on DOHC HONDAS.  Corroborated no seal needed.   Something was not right, this guys , all of them, supported some crazy, yet perhaps right idea that a part like this would work on both SOHC and DOHC , which could be, great, but the seal deal, this plug did not fit as tight as the stock cable, yet uses nos. eal or O ring ? Hmmm

   Checked Cycle X parts on display on their site. Same items as. i purchased, black, clear plugs, same mushroom head, like a bolt with a large head. Claming it fits 76-83 Honda 750's as well as others did.

    From looking at SOHC photos, head is as large as rim of tach drove port, covers it fit to size.

    In the case of the DOHC, head of plug is wider in diameter than tach drive port.  Body of plug is smaller than diameter of tach drive port, wiggles a little bit. Cable does not wiggle at all , yet they claim no seal is needed ?

    But problem , real problem is, since driver port is tilted forward, and since head of plug is larger than diameter of port, plug can not sit completely in port, far down enough to seal upper rim, and to allow groove on lower portion of plug ( like tach cable has ) to meet securing bolt allowing it to insert into valve cover.

    So this plug , claimed by all to work on all HONDAS 76-83, does not work. Monkey see, monkey do !

    All these clowns ("Joker Motorcycle Parts" ; "Cycle X" ; e-bays "4 into 1 motorcycle parts") are selling something without even taking the time to find out. Garbage.

    Here Cycle X photo on a SOHC :

[masiste]

On DOHC HONDAS this plugs can not sit and seal, because lower side of plug hits valve cover.

Plug would need to be either smaller to fit overall rim diameter of tach drive port, as in SOHC photo, or else, flaten one side of plug head, asw ell as bigger diameter of plug body, because it wiggles.

Had the issue with the head of plug not been there, I am sure plug would leak anyways. There would be nothing in there to stop oil from seeping out and leaking all over .

Photo of DOHC section.

[TOOLS1]

How about a photo of your DOHC installation?
TOOLS

[masiste]

Hi .

Here  2 photos I took with phone camera.

First, tachometer drive port. Look at lower side.  Unless plug had no mushroom head, the way it is built (plug) can not fit.

[masiste]

Here plug on port. Photo speaks for itself.

[shinyribs]

I wish I had been keeping up with this thread. As soon as I saw that pic of the plug I knew it was for a SOHC. If you can't find a plug for your DOHC I could make you one. All I'd have to do is mimic the end of the tach cable. Should be pretty easy. I actually pulled it off once already for a SOHC. ;)

[masiste]

 Thanks shinyribs.

   Did change the seal and used old tach cable which is not working ( cable ) but it stopped leak.

   I would definitely like a plug. I am going away for 2 months . Out of town, overseas to visit mother, but when I come back let's get on that.

   Will remind you.

   

[shinyribs]

Actually, that works out pretty well. I just ordered a new gauge unit for my DOHC so I'll be deleting my tach drive too. I'll make your plug while I'm making mine.

[TOOLS1]

I would just fill them in with some JB Weld.
TOOLS

[shinyribs]

lol. We know,buddy. We know.