Topic: I knew it was only a matter of time . . .

[kyle750]

 . . .  before my luck ran out on bolts 


Removing the gear shift cover and the bolts were in rough shape.  Over-tightened, repainted, rusted, and some have stripped heads.   3 did not want to move.  Of the 3 stripped bolts 1 came out with a regular screwdriver.  The 2nd was a  lower bolt and I used a vise grip and heard the wonderful crack of the bolt loosening and then came out easily.  The 3rd I had to use a dremel and cut a larger slot to the top of the head and then used a larger regular screwdriver and finally got it out.  Not always easy!

Quick questions on the gear shift assembly.  There is a thin gasket and after removing the cover I carefully cut out with an sharp x-acto knife that I can reuse.  The spring looks like it might be a  replacement spring  and does not look like very good quality? Also there was always a small amount of dripping oil from the lower cover for the last 3 months ever since I got the bike  and I understand that there is a small O-Ring that probably should be replaced? 

Thanks again for the assistance - other Honda owner's experience is always greatly appreciated!

[M 750K6]

Which screwdriver did you use. The heads are 'JIS' not Phillips or Posidrive. If you don't have them, get a set of JIS drivers. The fit to the heads is spot on.

Also, I've found the manual, not powered version of one of these invaluable for that initial loosening: https://en.m.wikipedia.org/wiki/Impact_driver
Make sure you get JIS heads with it. Not expensive.

I try not to re-use gaskets. Too many bad experiences! If you look on the CMSNL website there are 'exploded' parts diagrams that will put you right on gaskets and o-rings. I googled parts diagram for my model and got lucky with a free download that has been useful.
👍

[kyle750]

I have been using a JIS screwdriver and it has been working fine - except with the 3 stripped heads.  Those 3 were chewed up and rounded out and I could not get a bite.

[kyle750]

Gasket is a very hard rubber

[kyle750]

NOS Honda gear shift spring?

[newday777]

NOS Honda gear shift spring?

Wrong spring for the 750.

#12 is what you want to get if you are worried about your spring.

[newday777]

You really need to familiarize your self in using the part fiches, not relying on fleebay(many sellers are liers!)

[kyle750]

My mistake as I misread the item description.   Seller did not list this spring for the CB750

https://www.ebay.com/itm/205104223820

[kyle750]

Honda 24641-300-000 gearshift spring is out of stock on many supplier websites.  I could only find one seller who has them in stock

https://www.ebay.com/p/1350766789

[Stev-o]

You dont have an impact driver?!  It is a must when removing old screws on these bikes...only about $15...



And when replacing the old screws, a lot of us use SS socket head cap screws, you'll never strip one...

[MauiK3]

Always use anti seize on these fasteners.
Did you say you have Honduran's book? It's the best tool in your kit and will save LOTS of heartache.https://www.amazon.com/CB750-book-Putting-Them-Back/dp/0557310237/ref=sr_1_1?crid=1CAHQ8KMSE2RB&dib=eyJ2IjoiMSJ9.EbQoh2CINsEzyaGPQ7A8BvOEhmBVlpgMxPpC2MyITJk.08hQ3Vk1hGBkpmH1a90rP6skNq7PDvXOH5bhvIWOpPQ&dib_tag=se&keywords=Mark+Paris+Honda&qid=1744641868&sprefix=mark+paris+honda%2Caps%2C213&sr=8-1

[kyle750]

After today's battle with the bolts I will be looking to buy a high quality impact driver (with JIS  bits) tomorrow 

[beemerbum]

I have had substantial success with case screws on old Hondas using the Motion Pro "T" handle. It comes with bits for #2 and #3 JIS bits. It has worked for me when an impact driver has not.

[Stev-o]

After today's battle with the bolts I will be looking to buy a high quality impact driver (with JIS  bits) tomorrow 

Some drivers wont come with JIS bits, I bought mine separately. Vessel is a very high quality tool maker...


https://www.amazon.com/Vessel-NO-250001-Impact-Driver-No-250001/dp/B001WHOV64/ref=asc_df_B001WHOV64?mcid=2285e3b280e83f3ea5cedff02961cf00&hvocijid=5222963891759346647-B001WHOV64-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=5222963891759346647&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9028253&hvtargid=pla-2281435178298&th=1

[kyle750]

And when replacing the old screws, a lot of us use SS socket head cap screws, you'll never strip one...

I certainly can understand using hex head screws but decided on the traditional round head JIS screw set from Yamiya.  Yamiya already shipped the set and I should probably have the new screws on hand by the end of the week 

[M 750K6]

Yep, I'm the same. I'm fond of the old school look. Anti-seize would be a good idea.

[PeWe]

I remember when my stock X-bolts (JIS)  had to go on my CB750 K6.

Many of them had to be drilled off.
Drill so head fell off. Same with the countersunc x-bolts inside the shifter cover. Drilled the heads off. No collateral damage.

All JIS replaced by allen head bolts after that. I had lots of them at my job early 80's. M4-M8 in various lenghts.

Even my Mikuni smoothbore carbs got allen heads for top covers and float bowls.
It had been very tricky to remove float bowls with carbs mounted on engine when changing pilot jets, allen heads no problem. M4x12.

My oil pump upgrades the last 8 years. Drilled off the x-bolts.
Countersunc allen head and hexagon bolts.

Easy to service a bike restored to be frequently used.

Different with a fully 100% stock,  a beautiful museum bike for less riding.

My K6 got the valve cover removed very frequently a few years ago

Both my CB750 have frame kits so valve cover can be taken off with engine still in frame. Head and cylinder too.

[newday777]

Always use anti seize on these fasteners.
Did you say you have Honduran's book? It's the best tool in your kit and will save LOTS of heartache.https://www.amazon.com/CB750-book-Putting-Them-Back/dp/0557310237/ref=sr_1_1?crid=1CAHQ8KMSE2RB&dib=eyJ2IjoiMSJ9.EbQoh2CINsEzyaGPQ7A8BvOEhmBVlpgMxPpC2MyITJk.08hQ3Vk1hGBkpmH1a90rP6skNq7PDvXOH5bhvIWOpPQ&dib_tag=se&keywords=Mark+Paris+Honda&qid=1744641868&sprefix=mark+paris+honda%2Caps%2C213&sr=8-1

Far cheaper directly from LuLu(link in Site Sponsor section)
for Hondaman's book (not Honduran as you auto spell check does!)

https://www.lulu.com/search

[kyle750]

Old Gear Shift cover will be stripped of the old paint and refinished today.  Looking forward to receiving the new bolt set 

[Don R]

 I'm an outlaw when it comes to the case screws, I use a Snap On #3 bit in a 3/8" drive socket and a Craftsman C3 impact driver. When the screws come out, they are usually stuck on the end of the bit.
 I do have a set of Vessel JIS screwdrivers and they do work well also.

[kyle750]

Very strange coincidence as I am looking at a Vessel Impact Driver with JIS bits from a seller from Japan.  Normally delivery from Japan to Thailand is very quick.

Also looked at a local Thailand made impact drivers but decided on the Vessel from Japan. 

[HondaMan]

Just a mention: the original finish on the transmission, alternator and clutch-side covers was smoothed (almost polished) and then clear lacquer sprayed on them. They weren't painted like the engine cases, cylinders and head were.

[Kelly E]

I have a set of Vessel JIS Impacta screwdrivers and they work great but, I've had way better success using a DeWalt cordless impact gun and JIS bits.
I replaced all of the case cover screws in 30 minutes on the 81' GS 1100E without breaking one. This was a bike that sat out exposed in a carport for 16 years. It was so dirty we had to wipe a thick layer of dirt off the gauge just to read the mileage.
We've done several bike resurrections using the DeWalt to remove stubborn screws and bolts since then with great success and you won't break anything with the hammer.

[kyle750]

Just a mention: the original finish on the transmission, alternator and clutch-side covers was smoothed (almost polished) and then clear lacquer sprayed on them. They weren't painted like the engine cases, cylinders and head were.

Many thanks for the additional information on the covers. I greatly appreciate your expertise and very detailed knowledge.   I still can't tell what is painted and what is clear coated. Stripping the coating now and it's coming off easily.

[kyle750]

I replaced all of the case cover screws in 30 minutes

If I'm lucky it might take me 30 years