Topic: 1983 CB 1000C restoration

[Flyin900]

This is my own bike that I have owned for quite a few years and wanted to bring it back to it's original glory mostly cosmetically with some mechanical work too. It did have a valve issue on the #4 cylinder and when I pulled the head one of the exhaust valves was slightly burnt, although the seat was still really good without any damage.
I totally refreshed the head with a machine shop 3 angle grind and all new Viton valve stem seals and did some clutch work on the basket. These tend to start a clutch rattle over time as the rubbers internally in the basket shrink from age and dry out. At idle there is a rattling sound that is worse with poorly synced carbs.

A member from Holland on the CB1100F DOHC forum has a solution with a kit to replace the rubbers with a little machine work on the basket to get it apart and install new dampers. I did a full front end rebuild with the TRAC anti dive system and Progressive springs and fortunately the forks have a factory brace already installed. The rear air shocks were rebuilt with new seals and fluid to match the front fork rebuild with fresh parts and oil.

The rest was all paint and time end effort to get it looking factory fresh again. With only 29000 Klms or about 18K miles it is ready for another 30+ years of fun.

[MoMo]

Looks good, right now I have a CB900C in my shop that the customer wants to get back on the road. I always liked the model other than the goofy hi/low range selector...Larry

[TomsK8resto]

Nice looking bike.  What are these bikes like to ride?  Do you leave it in low range for around town riding and high range for open road?   I've always been curious as to what Honda was thinking when they designed this feature. 

Tom

[MoMo]

Nice looking bike.  What are these bikes like to ride?  Do you leave it in low range for around town riding and high range for open road?   I've always been curious as to what Honda was thinking when they designed this feature. 

Tom

Tom,  they make fine open road cruisers, very smooth and powerful enough for two up with gear.  Low range is totally unnecessary-I have no idea what Honda was thinking.  Why would a 900 or 1000cc bike need a low range  :-?

[Bankerdanny]

The add on box was how Honda converted the engine to shaft drive. I suspect the dual range thing was an 'as long as we're at it' moment.

[TomsK8resto]

Are they pretty durable bikes?  I've seen a number of them on CL and it seems like sometimes they are difficult to sell.   Do they have any major weak points that you need to be aware of it looking to buy one?  As you guys said, it seems it would be a pretty smooth ride.  Do they handle similar to our SOHC 4s?

Tom

[MoMo]

Are they pretty durable bikes?  I've seen a number of them on CL and it seems like sometimes they are difficult to sell.   Do they have any major weak points that you need to be aware of it looking to buy one?  As you guys said, it seems it would be a pretty smooth ride.  Do they handle similar to our SOHC 4s?

Tom

heavier handling, definitely not for the canyon carver.  No problems that I'm aware of.  Just not all that desirable Tom, but a good, trustworthy rider. like any Honda-regular maintenance and oil changes and you can ride to infinity and beyond.

[rickmoore24]

Nice bike Flyin!

[Flyin900]

Well to answer a few questions these bikes are IMO the next level that the SOHC 750 should have achieved when the competition started offering DOHC bikes in the mid 70's and Honda stuck to the SOHC design till it was really long in the tooth. In the CB F series which were a chain drive 5 speed motor that started as the CB750F then 900F and culminated in the CB1100F they were AMA racing champions for many years in both the US and Britain.

The CB900 Custom shaft drive version came about as an offshoot for a cruiser style bike and as noted by Bankerdanny the chain drive off the CB 900F motor needed to be converted to the opposite side to accommodate the Goldwing drive line assembly on the right side. A jackshaft was employed to accomplish this and a two speed transmission was incorporated into the set up. It only made sense as a single speed really wouldn't have taken full advantage of the design set up, plus there was a high range ratio engineering change for the 82/83 model year that reduced the RPM in high range another 500 rpm.
Starting off in high range while possible isn't the best course, since it does stress the clutch and can lead to stalling when not expecting to have to slip the clutch and rev more to get the bike to pull away from a standing stop.
These bikes are super smooth with rubber mounted motors and very minimal if any vibration. The technology of DOHC's and four valves per cylinder are in a different class too producing a claimed 85HP on the CB900C and 89HP on the CB1000C and 105HP on the CB 1100F. These motors can also be modded on the CB1100F out to over 1300cc's in size. Riding two up is a breeze with no noticeable difference on flat terrain since the bike also produce about 64 ft lbs of torque on the smallest 900cc version.

I have restored about 8 of these models over the past 5 years and they are an underappreciated bike and as also noted they don't seem to have great demand currently, yet everything changes. If you can pick one of these up cheap I can highly recommend the ride and the power and howl at the 10K redline! 

[MikeSimon]

Well to answer a few questions these bikes are IMO the next level that the SOHC 750 should have achieved when the competition started offering DOHC bikes in the mid 70's and Honda stuck to the SOHC design till it was really long in the tooth. 
 

Here is a little insight into Honda's model and product strategies which I obtained while doing extensive research about the CBX and the DOHC Fours.
This included meetings and telephone conversations with many former and current Honda employees both from American Honda sales and manufacturing people from Marysville:

In the mid-70s Honda's priority was the development of a large displacement "Sport Tourer" to compete with BMW. The Germans had introduced their /6 line with a 900cc on top. This resulted in the GL1000, (which at one time was contemplated as a flat 6) introduced in late 1974. Looking intensely to Europe, Honda got somewhat caught by Surprise by Kawasaki's Z1 and immediately after the GL design and development was finalized, started working on a DOHC Four in two displacements - a 750 and 900cc. Mainly because at the time when R&D began, Japan had a restriction of 750cc max for the domestic market. Kawasaki's spy network seemed to have worked better, and when Honda learned, that Kawasaki was planning an in-line Six as a response to the GL1000, they crash-started the CBX development to have that bike come out in 1978 as an early 1979. This and some changes to the organization and location of the R&D facility were the main reasons the DOHCs did not see the market until 1979.
The DOHC-Fours are indeed the true heirs and logical successors of the SOHC-4.

[ekpent]

 Its interesting also that Kaw was first going to come out with a 750 four, a few were made as I think I saw a Jap market example, but waited a little longer and bumped it up to the mighty 900 Z to really put the hurtin' on Honda and set that bar higher.
   Mike are you by chance the guy I see advertising in some publications for CBX literature etc. ?

[MikeSimon]

Its interesting also that Kaw was first going to come out with a 750 four, a few were made as I think I saw a Jap market example, but waited a little longer and bumped it up the the mighty 900 Z to really put the hutin' on Honda and set that bar higher.
   Mike are you by chance the guy I see advertising in some publications for CBX literature etc. ?

The Z1 was a 750cc  for the Japanese domestic market, due to the displacement restrictions there. No, I am not the guy selling CBX literature.
Where is he? On ebay?

[kmb69]

.....
The Z1 was a 750cc  for the Japanese domestic market, due to the displacement restrictions there. No, I am not the guy selling CBX literature.
Where is he? On ebay?

Pretty sure the Z1 was originally designed to be a 750cc until Honda beat them to the punch and they held back and went up to 903cc.
The Z2 was the 750cc version that was sold in the Japanese market and maybe others.

[MikeSimon]

Yes, my statement was probably worded wrong. The 750cc "Z1" was named Z2 for the domestic Japanese market.
With what bike did Honda beat Kawasaki to the punch in 1972/73?
Remember that Kawasaki had the world's fastest 750 in 1972 in the MachII H2 two-stroke triple.
Very unlikely that they would design a 4-cylinder 4-stroke with the same displacement.

[kmb69]

Yes, my statement was probably worded wrong. The 750cc "Z1" was named Z2 for the domestic Japanese market.
With what bike did Honda beat Kawasaki to the punch in 1972/73?
Remember that Kawasaki had the world's fastest 750 in 1972 in the MachII H2 two-stroke triple.
Very unlikely that they would design a 4-cylinder 4-stroke with the same displacement.

Some time back I read that the Z1 was originally being designed as a 750cc 4 stroke for International markets due to upcoming environmental regulations in other countries that their 2 strokes couldn't achieve. The article stated the Z1 development started in the same time frame as Honda was just releasing the SOHC 750. I don't think it was so much performance related until they decided to one-up Honda with a 4 stroke. I'm not knocking Kawasaki, I bought a new Z1 in 1973 while working as a Honda Service Manager. Took quite a bit of razzing over it but I was disappointed that Honda had not already produced a bigger bike and I loved my Z1. I still own 3 Z1's (one of them is 1972 VIN Z1F-00264), an H1, and an H2.

[ekpent]

 Here is some more info on project code name " New York Steak"---  http://www.kawasakiz1.com/HISTORY-of-the-Kawasaki-Z1.html

[kmb69]

Here is some more info on project code name " New York Steak"---  http://www.kawasakiz1.com/HISTORY-of-the-Kawasaki-Z1.html

That's how I remembered it! Thanks

[MikeSimon]

Sorry, I am still not convinced. This is just another story someone wrote. During all my years of involvement in Japanese motorcycles and trying to clarify some of their "history", I found that a lot of things are shrouded in the typical oriental mystery. It is a culture thing. The praise of achievement and individuals always takes priority over the truth. And then there is the U.S. the "homeland" of the conspiracy theory. Stories are being invented because people have the need to be known to know something and want their 15 minutes of fame. That adds to all of it.
I am sure, you all remember the controversy a few years ago - may be it still lingers on - whether the early CB750 Four engine housings were really "sandcast". Someone made a statement in a book that they were not. Soichiro Irimajiri was the head of the R&D group at Honda when the CBX was developed but he did not participate personally in the development of the bike, thus was not the "father" of the CBX. Japanese respect for authority dictated all credit going to him. The Suzuki GS1000S was never officially called a "Wes Cooley Replica." Wes Cooley's winnings on that bike came AFTER the GS1000S was introduced. I find it hard to believe, that Kawasaki designed a 750 inline four 4-stroke  at a  time when they had not even introduced their 750 H2, because they were expecting the two-strokes would be outregulated.

[ekpent]

  Couple more "myths" I guess
http://www.motorcycle-usa.com/2007/07/article/memorable-motorcycle-kawasaki-z1/

http://www.motorcycleclassics.com/classic-japanese-motorcycles/kawasaki-z1-prototype

[kmb69]

  Couple more "myths" I guess
http://www.motorcycle-usa.com/2007/07/article/memorable-motorcycle-kawasaki-z1/

http://www.motorcycleclassics.com/classic-japanese-motorcycles/kawasaki-z1-prototype

Kinda interesting that all these "myths" pretty much carry the same storyline! 

Also interesting that some still question the "Sandcast" 750's. They were.
The prototype CBX engines were "Sandcast" as well. One just sold on eBay last year for stupid money.

[MikeSimon]

Well, I'll be! That's what I like about communicating with other enthusiasts! You always learn something you did not know.

[Ncdan]

Hello fellow members.
I need a set of headlight stays for a 1983 Honda CB1000C.
If any has  a set they will part with email me at, dgps3@yahoo.com
Thanks
Dan

[MauiK3]

Wow, a thread picks back up after all those years!
Nice CB

[Ncdan]

Hey fellow CB1000c lovers.
I am in need of a backrest/luggage rack that was a hondaline accessory.
This attaches directly to the existing factory grab rail.
I’m willing to pay a premium for this part.
I’m Dan and my email address is Dgps3@yahoo.com
Thanks