DOHC cb750 starter install

To start: I have a '82 SS with a seized starter. Rather than taking it apart I decided to get a second hand one that was tested and in good condition for a great price. (I tested the old one and the spindle gear wouldn't even spin)

Getting the old starter out wasn't too big of an issue. It slide off the gear just fine and with a little bit of force I was able to get it out just fine. Not really anything to question i didnt have to fight it too much. It pushed straight out of the gear > tilted the back of the starter and it came out just fine. 10/10 easy.

I'm having trouble getting the new one in. Are there differences in the DOHC (79-82) starters? It sits in a weird angle and I cannot for the life of me slide it back in. I'm afraid to really put any mustard into it because I don't want to score or damage the engine casing that the spindle gear goes through. That side cover is off and the gear the starter is suppose to line up with is off as well to make it easier.

I hope this is easy to follow...

Are there differences in DOHC starters?

Do I just need to get something to help leveraging it in there? I tried a local search and some googling and couldn't find anything related to my issue. I'm hoping i'm just being too cautious and just need to ram it in there.

Parts fiche shows 31200-425-008 or -018 (probably different vendors) for '79 - 82 Ks and Fs. I suggest taking some measurements from the old one to make sure you have the replacement. BTW, there are several CB750 dohc-specific sites.

the starter gear has probably moved and not meshed

i always do them by pulling the pulse generator cover off so i can guide the gear back on the starter and make sure it is on properly

while you are in there you also want to check the three starter clutch bolt are tight if not pull the mechanical advance unit

check the bolts and if they are good use some blue loctite and torque them down

most of these come loose than make a noise you would swear was a rod knock

this will show you and you can see the starter gear in the upper right behind the idler gear

https://www.youtube.com/watch?v=V5xDlTqhInk

CXMAN I appreciate you taking the time on your response. Funny enough I've come across that video on youtube trying to find any clues or hints on getting this baddie in. The cover is off and that gear has been taken off as well so I know we can eliminate that one. I had checked the bolts you had mentioned and they are tight and snug so I appreciate the heads up.

A couple things, I handed over the original starter so I dont have that with me anymore. (Learned my lesson on that one!)

pidjones said:

Parts fiche shows 31200-425-008 or -018 (probably different vendors) for '79 - 82 Ks and Fs. I suggest taking some measurements from the old one to make sure you have the replacement. BTW, there are several CB750 dohc-specific sites.

Click to expand...

So on the back of the starter I have it lists ' Mitsuba SM-226 12v 0.6kw'


I have tomorrow off so my plan is to get some leverage and try and mustard that thing in there.

that is a mid 70 like 75 ish cb750 sohc starter

its the wrong one

see

https://www.ebay.com/itm/HONDA-1975-CB750-CB-750-STARTER-MITSUBA-SM-226-0-6kw-5-29/131229990265?hash=item1e8deabd79:g:gCUAAOxyu1BTkxrQ

you need one like this

https://www.ebay.com/itm/81-HONDA-CB750-DOHC-ENGINE-HM128-2B-starter-motor/292937785994?hash=item443473e28a:g:kmwAAOSwyeNcORU9

i have 4 of these bike and only one spare or i would try to help you out sorry

CXMAN

You make forums like 'DOTHETON' incredibly valuable for people like me. Here I am thinking I just need to man up and jam that SOB in there - I appreciate your knowledge and wisdom.

Looks like im going to try and give this one back and get the correct one.

SO, for keywords if anyone else runs into this problem. SOHC and DOHC starters are clearly different - obviously not interchangable. Looks like I was sold a SOHC starter and not the DOHC starter.

Thanks again for chiming in on this thread.

dohc starters have 2 bolt holes at the back to hold them down and 2 tapped holes on the top to hold the starter cover down

Also, the SOHC starter doesn't have a 10mm bolt to take the power wire off. Does that make sense? Maybe thats another characteristic to look out for regarding differences.

I noticed the starter i had taken out of the bike I was able to take the power wire off the starter. The incorrect starter that was given to me has a fixed power cable on the starter.

Anyways, tomorrow im heading to that shop where i got the SOHC starter. If i end up getting the correct replacement I will respond to the thread and close this up. Hopefully no more issues! Thanks again

Problem solved!

You guys im back on the road. So the back of the DOHC starter has a bit of a cut away where the bolts go through. The thing laid in parallel and slide right in. What a relief.

there you go no muscle up needed