There's a lot of great stuff on this site. OK, there's a lot of silliness, too, but also there's a ton of great information that good folks have worked hours on to provide, with no compensation or hope of riches or fame. When you find some of this great information you may want to share it on other sites. We understand. After all, the driving force behind all these efforts to is to share information. However, it would be very appreciated if you ask the author, if possible, for the use of the information and give proper credit where credit is due by correctly attributing the the source of the information. We can't force you to do this. Copy & Paste is just too easy. But, failure to do it is simply bad manners.
Please read this thread, and click on "Enter the Forum" at the bottom of it.
Last edited by D-Day on Tue Mar 22, 2011 6:38 am; edited 1 time in total
Joined: Jul 24, 2007
Location: Studio City, CA
Fri Nov 27, 2009 10:05 am
New members Welcome! Old members welcome back!
This document changes from time to time, so please check it occasionally. If you think of something that would help in here, please PM me.
This info is put here to help you, but it only works if you read it and pay attention and do the things outlined here. If there is something that is already explained in here, we are reluctant to explain it again over and over in posts.
This forum is a computer only site, and is specific to the 1979 to 1983 Honda DOHC CB750/900/1000 Custom and other models with the inline 4 air cooled DOHC motor. Posting about other types should be done in the off topic area or some other forum that supports your model.
As a computer site, any functionality by smartphone is accidental. I don't use my smartphone here, too damn small... so don't expect support for phone related issues here. I/we couldn't care less. I run dual 27" or 23" monitors, or a 17" laptop. Don't care about tiny whatever, sorry.
Put Your DOHC Bike Model(s) in your Signature
This is a site requirement here, so please make sure you do both steps properly. Once you've done it, check to make sure your sig actually does show up in your post. This lets us know you actually did read this info, and it tells us what specific bike model people have when they neglect to do so in their posts.
Put the year and model of your DOHC Honda motorcycle(s) relevant to this forum in the signature section of your profile. If you don't have a Honda DOHC motorcycle, but work on one or several for friends or as a professional mechanic, put that information in instead. Or, likewise, if you don't yet have a DOHC Honda, put that in your sig. You may include the name of your business in the sig, but don't turn it into an advertisement or link, this isn't a place where we allow advertising.*
To do this, open your Profile page with the link near the top of every forum page, then scroll down to the "Profile Information" section and find the Signature: area. Fill in your information in the box. We don't need every bike you ever owned or currently own in your sig, just the relevant one(s) is (are) adequate.
click on the pic
Then in the "Preferences" section, click the tick box labeled "Yes" next to "Always attach my signature:" and save your profile by clicking on the "Submit" button near the bottom of the page.
When you post, you need to make sure the checkbox labeled "Attach signature (signatures can be changed in profile)" is checked. It should be checked by default, but if it gets unchecked, you need to re-check it for your sig to appear. It is supposed to stay in whatever state it was in the last time you posted. So it should always be checked. See the pic below:
click on the pic
Also make sure you do the following:
In order for your signature to show up in your posts you also have to confirm that the checkbox that's labeled "Attach signature (signatures can be changed in profile)", just below the Quick Reply box at the bottom of threads, is actually checked when making posts. You should then check to see if you have your sig showing at the bottom of every post.
You can also edit old posts and turn on the "Attach signature" checkbox on an old post, but the signature will only appear in posts that have had that checkbox switch checked on as well as the proper entries in the Profile.
Also, while you're in your profile page, be sure to check and adjust your other preferences, such as for email notification for replies and PMs, and set your time zone for your browsing convenience. Your avatar can also be set in the profile. Its width x height must be no greater than 120x120 pixels, or we will delete it.
If you didn't already, please make sure you filled in your location with the city and state of your primary residence. Just USA or UK is not really going to help us help you if we have members that can suggest services or rallies in your area.
* Advertising *
We don't allow advertising here. If there is to be any advertising, we, the operators of this forum, will provide it and make our own money from it. We don't do advertising however, and we don't intend to in the foreseeable future.
There shall be no links to your business in threads, or in sigs, or your employer's business.
There shall be no bias in posts due to one's ability to be able to "get it for you wholesale", or any other way. If someone asks you if you can get something, you should reply for them to email to you or for them to PM to you. If you want, you can put your email address in your sig, but it should not be an obvious business email address, like email@example.com. a "masked" email address is fine.
If it happens to be asked in a thread what one does for a living, it is of course, permissible to declare that you sell bikes or parts, but there will not be any discussion in the open forum of any specific item that one sells. That should be done in PMs or email. We want no coloring of any advice to be due to anyone's business interests.
The staff here, or other posters, may recommend you contact one of our site members (in a thread) that is known to sell something. That contact should be done via PM or email.
Picture Sizes in Threads
We have a limit for picture sizes displayed directly in threads of 640 x 480 (or 480 x 640) pixels. We still have dialup members that live in areas that don't have broadband, so no huge pictures are to be displayed directly in threads. Links or clickable thumbnails to large pictures are acceptable and encouraged however, as long as the thumbnail isn't over 640x480.
Also, pictures that are too small are just about worthless. Don't show pictures in such a small size to be able to see the detail on a normal computer monitor running an XGA display. Not everybody here has ultra high tech stuff, or the money to get it, or they live in an area so far out they can barely even get dial-up access. So old slow compatibility must be adhered to.
Picture Sizes in Signature
Pictures displayed directly in the signature are permissible. Several can be stacked end to end (but not vertically) and the total area for all signature pictures should not cover more than 120 pixels in height and should not cover more than 640 pixels in width. Clickable thumbnail pictures in your signature are possible and encouraged. The tags (the codes between the square brackets [xxx] ) in your signature coding need to be in lower case or they won't work.
Linking Other Forums in Signature
Links to other forums is not permitted in the signature by general members.
Other Information in the Signature
Generally, brevity is preferred in the signature.
The signature is not a billboard on which to advertise.
You may put your email address there if you wish.
A clever quip is OK in the sig, but should be brief, and not offensive in nature.
Mocking another member in your sig is prohibited.
Quotes of other members postings meant to mock them is prohibited in your sig.
Failure to comply will result in your sig being modified to remove the offending part. Continued abuse will result in a disabled account.
Avatars should be no larger than 120x120 pixels. Any larger starts to expand the left margin of every page that you post in, making it hard on users with small monitors. They also shouldn't be offensive in the workplace. Offending AVs will be removed without discussion.
Fonts In Posts
Do not use all CAPS, all bold, all italic, or all large fonts except for emphasis, just use the default black font. Your posts are not that much more important than anyone else's posts. Using all caps in a post is considered yelling and rude, if for no apparent reason.
If you have difficulty reading small fonts, most browsers have a zoom facility in the view menu that will make everybody's posts readable.
Failure to comply with these posting rules will result in the removal or resizing of the post, picture, or AV by forum staff, at their discretion.
Last edited by genesound on Fri Jan 03, 2014 8:19 pm; edited 6 times in total
Joined: Jul 24, 2007
Location: Studio City, CA
Fri Nov 27, 2009 5:03 pm
Eligibility for posting in the For Sale section
Members offering items for sale here must be in good standing with the board and have a minimum of 10 quality technical posts before posting items for sale here. Highly edited posts with the bulk of the message removed or a lot of complaining will not be counted towards the requirement.
Friends and others already known by members or management, or anyone at our discretion may have this requirement waived by the Administrators. PM one of the Administrators or Moderators for assistance.
The same principal applies to posting links to your own ebay auctions. This is a participation self help forum, not a place to come place ads to sell your stuff.
Hijacking other's threads for your questions
If you have a technical question, start your own new thread. Don't just start asking your question in somebody else's thread; it's rude, and causes confusion on who's question is being answered in subsequent posts. You will get better results and more complete attention with your own thread, and so will the guy you're hijacking. And if someone starts asking their own questions in someone else's thread, don't answer them, politely ask them to start their own thread. and they can link to the other one if they'd like to compare information, but don't just take over someone else's work.
If there is an old thread that is almost like what you want to know or say something about, don't just hijack the old thread, start your own new thread. You can certainly link to the old one as a reference if it helps you explain your issue, but don't just start posting in an old thread it like it was new yesterday. It just adds to the confusion, and it's not your thread either.
We discourage any new posting in old threads, unless the original poster is adding something relevant like an update to their own thread. In many cases, the original poster doesn't regularly post anymore, so will never see your post anyway.
We do encourage others linking to old threads or posts for information purposes in new active threads, but have found that one post in an old thread leads to another, then another, until the thread takes on a different life altogether, which is unnecessary, it should just all be in a different new thread.
Please just use the old threads for research, and feel free to refer to them in other threads, just don't start a new line of discussion in someone's old thread.
If you have a technical question, post a thread about it. Do not PM the staff or others looking for "special handling" unless you're invited by somebody to do so. We aren't the concierge desk, and besides, if you have a question about some aspect of motorcycle maintenance or building, other people may benefit from the discussion as well; that is what the open forum is for and why it is here. Also, someone else might come up with a better solution than the person you PM, so that person get's to learn something too.
If you need to discuss price or other transaction details, then a PM with another member or staff is proper and preferable to trotting out one's business in a public thread post in front of the whole membership. Also personal howdies and such are OK in PMs. Private matters are, of course, what Private Messages are for.
Do not PM the "admin" account. We don't often read it and PMs addressed to "admin" will be ignored. If you have business with the forum, instead PM one of the staff directly; staff usernames are listed at the bottom of every page.
If a forum moderator or administrator sends you a private message, it is expected that you, the member, will read it and answer forum issues that the moderator or administrators may ask, and that the member will comply with any reminders of rules or other behavior issues as indicated. Failure to do so are grounds for loss of access to one's account.
When you send a PM, it goes in the "outbox" where it remains until the recipient opens it, at which time it will move to the "sentbox". Don't freak out because it's still in your outbox, it just means that the recipient hasn't read your PM yet.
Use the Search
Learn to use the search function. We get PMs from people about questions that have already been asked and answered many, many times, and that's just plain annoying.
Check the stickies and announcements in the forums.
Many good posts and forum tips are put there.
Repeating Posts in Multiple Sections
Do not start the same thread with the same question in the same or several different sections, even with slightly different wording. It just gets confusing, and the moderators will delete the duplicates. One thread on a subject per user at a time please.
If you go to the main forum index, there is a link at the upper right of the page called "View posts since last visit". If you use that you will be able to see all the new posts in all the sections of the whole forum since your last visit. The url of that link is:
You may also want to bookmark it "750C Forum New Posts" or something similar. I actually use that as my home page in my browser.
Joined: Jul 24, 2007
Location: Studio City, CA
As a prerequisite to posting, we require that you read and become familiar with the Honda Shop Manual for your bike and this thread. There is stuff in these that you won't find unless you get familiar with the layout of them. And we don't take lightly to typing out answers over and over to the simple questions that are readily available in the Honda Shop Manual that we have here, or in this thread's message.
We have the Honda Shop Manuals with their Wiring Diagrams in pdf form available as Announcement listings in our Technical Documents section.
When using the Honda Shop Manuals, you need to look in the addenda for all the stuff pertinent to your year and model. The Honda 750 book was written for the 1979 K, then there are add-ons for the various other 750s and years. Also you might need to look at all of them. If something was updated in the 1981 version, they didn't necessarily include it in the 1982 addendum, you have to get it from the 1981 section. They are incremental, not all inclusive.
Same goes for the 900 book, it was written for the 80 900C, the other years and models are add-ons in the addenda.
We also have the Honda Common Service Manual in the Technical Documents area. It has more general motorcycle maintenance and "how stuff works" type information. If you don't have a lot of background in motorcycle mechanics, you should read up on this one too.
The Owner's Manuals for several models are also in the Technical Documents section. There is not a lot of difference in them, so find one similar to your model and read it, until we might get all the models available.
Partzilla, Parts Pit Stop and numerous other OEM Honda parts dealers in the US have their parts fiche online with the OEM part numbers, availability (sometimes not accurate), and pricing, that can help you determine what parts are necessary, what parts are still available from Honda, and what bikes use the same part numbered parts in common. Please avail yourself of these resources yourself instead of asking someone else, who then has to go look up your parts on one of these places and read the information back to you.
Proper valve clearance is probably the most important maintenance issue to keep these motors running next to frequent oil changes and cam chain tension adjustments. Valve clearances need to be checked every 4000 miles or so. Most mechanics and long term owners of these bikes agree that the ideal valve clearance for these DOHC motors is .005" or .13 mm, regardless of what the book says. So, somewhere between .004" to .006" or .10 mm to .15 mm is acceptable. The book says .002" to .005" or .06 mm to .13 mm and those low numbers are just too tight and can lead to burnt valves.
The 25 mm diameter shims these motors use are commonly made from 2.3 mm to 3.5 mm in steps of .05 mm. On real Honda OEM shims, the decimal is left out, so what Honda calls a 280 shim is actually 2.8 mm thick. The in-between sizes with sizes that end in 2s and 8s like 272 and 278 were never sold over the parts counter and were only ever available in new Honda motors from the factory.
NEVER turn over the motor without shims in ALL the buckets! The cam lobe will bend up the bucket and the valve will stick open, and possibly hit the opposing valve and then you can have bent valves. Lobe damage can also occur.
Ethanol and Crappy Fuel
These bikes need to be run at least once a week with this pretend gas nowadays. If not, you better keep something in the fuel to stabilize it or the ethanol will evaporate and the residue gum up your carbs.
You can use Stabil, Startron Enzyme Treatment, even Seafoam will help. There are others.
If you do a lot of short trips or haul ass canyon rides, or city freeway rides, with lots of hot/cold cycles, oil changes should probably be done at closer to 2000 miles or less, regardless that the book says 4000 miles. These air cooled motors can totally contaminate the oil much quicker than 4000 miles. Some guys even say to change it every 1000 miles. Personally, I smell and feel the oil. Once it starts to stink like exhaust and gas, or show any other contamination like water, I figure it's time for a change. Running it past that point is asking for premature wear. You can also rub it between your fingers and begin to feel some fine grit. Even though there is still plenty of viscosity left, the oil is too contaminated for the filter to get it out, and that stuff is wearing inside your motor like rouge.
Longer continuous rides, like 5 days of 700 mile days or so, can probably be done on one oil change, but keep an eye on the oil level, it will probably eat a little oil. Be sure to feel and smell the oil every morning before you start out to make sure the oil hasn't turned into liquid polishing compound or is thinned out like WD40.
Oil behind the ignition cover
When you open the ignition cover, and find oil in there.... It means your bike probably has oil in it; because yep, there is supposed to be oil in there. The starter clutch and gear is also in there, and it needs the oil. That's why there is the o-ring seal around the small cover too, to contain the oil.
Also, never turn the motor over with the thing that looks like a 24mm nut under the ignition cover! It is not a nut. If you turn over the motor with that you can break off the locating pin for the ignition rotor, and then the ignition will not stay in time until it's fixed. Only turn over these motors with the alternator rotor bolt on the other side.
When setting the front cam chain adjuster bolt and locknut be very careful, the hole threads strip very easily. We get numerous people a year having to repair these holes and it is possible but very difficult without removing the motor, so use 2 fingers on the wrench on that bolt and locknut.
When adjusting the "A" cam chain, use the "static" method as described in the cb900 manual, or the method described in the 1981 addendum on page 25-20 for the cb750 manual. It's also the default method in the cb1000c and ch1100f manuals. Basically it's done with the motor not running, and cold. There are also numerous threads describing the procedure and variations on the forum. The running method they previously specified doesn't really work well at all.
Silicone sealer, case sealer, gaskets, left handed threads
Also, DO NOT USE SILICONE SEALER OR RTV IN YOUR MOTOR, OR ON GASKETS, OR INSTEAD OF GASKETS!!! The oil will make it soft and swell up. It will break off in chunks like boogers and be washed down to the bottom of the pan where it will plug up the oil screen. Your motor will starve for oil and blow up! Don't do it!
Get Hondabond 4, Threebond 1194, or Yamabond. These products are made for motorcycle use, and will not be a problem. They are available at motorcycle shop or many online vendors, even Amazon.
All Honda paper gaskets go on dry, and all rubber seals can use a coat of grease. No Silicone bathtub or whatever sealer!
There are no left handed threads on these stock bikes at all!
Dimentions and posting standards
When posting about dimensions, please, give the unit of measurement. We tend to use metric AND imperial here, so it's important to state the unit of measurement! Trust us, there has been plenty of confusion on this in the past and the signal to noise of useful information becomes abysmal, and when 10 people get confused about something that could be easily avoided, it's much simpler if the unit of measurement is just specified in the first place.
Also, here in the US, most of us tend to have imperial feeler gauges, but of course we use metric shims and tend to convert a lot, so specifying the proper units can be very beneficial for those that are trying to follow along.
If you want to use pod filters on your stock CV carbs or recommend pods (pods being the individual air filters that clamp onto the intakes of the carbs, in lieu of the airbox), please look to another site for advice and help on this issue. Here's a sticky written by one of the founding moderators on the subject:
Pod Sticky Announcement
Our official position here, and our normal advice on carbs is to run stock jetting and needles with an unaltered airbox and a paper air filter in it. Time and time again, since the 80s, it has been proven that if you are going to use the stock Keihin CV carbs that come with these DOHC Hondas, they will work the best in this manner. They even self compensate for most pipe changes due to the way they work.
We don't wish to get into long discussions and rants about this and will not recommend setups and settings for running pods. Also having pods on a bike we're trying to diagnose tends to make diagnosing other issues and/or maintenance issues almost impossible to troubleshoot. If the reason the bike runs like crap is because there are pods on it, and the carbs are so far out it will barely run, it's almost impossible to figure out that the coil is shorting out. It's difficult enough to fix bikes over the internet without that pod issue screwing up the process.
Old side cover grommets get loose, and a hard slippery surface, and your precious sidecovers, made of unobtanium, will fly right off the bike while you ride!!! Be sure to check your side cover grommets and replace them if the side covers are the least bit easy to remove. When they are adequate (meaning NEW) the sidecover will be difficult to remove, and many have damaged their sidecovers from tight grommets. Put your finger around the back side and push the post out or otherwise make sure you don't break your sidecovers getting them off when the grommets are tight and new.
Chopper, bobber, and cafe guys
If you are into choppers, bobbers, or cafe bikes, we now have a section here for you. This is a new area and venture for us so welcome and we hope you enjoy your time here. I look forward to meeting new folks and learning some new stuff and seeing new ideas.
The Deuces Wild site is still a very good site for choppers and wildly modded stuff, and they have some real cool people there too, so let's not forget our cousins over there either.
These guidelines and information have been developed over a period of time to help make this forum a more enjoyable and educational experience for everybody. The intent is not to be bossy, but to help cut down on answering the same basic questions over and over, keep the threads viewable and readable to people with smaller and slower computers, and help avoid newcomers' and others' confusion.
And remember, you are under no obligation to take our advice, and we are under no obligation for it to be correct.
Last edited by genesound on Sat Jan 29, 2011 3:31 am; edited 3 times in total
Joined: Jul 24, 2007
Location: Studio City, CA
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If you have to wear stockings, make sure that you wear some that fit you very well and are not too large or too small. Wearing the wrong size can make you very uncomfortable and it does not look good for you if you have to adjust them in public areas.Only buy clothes that are flattering to your figure.
Do not think that you must have every fashion trend that is available, even if it does not look good on you. No matter how trendy an item is, if it is not flattering to your figure, don't consider buying it.If you want to bring your hair up from your shoulders, consider an simple up-do.
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