Topic: The 1970 Daytona CR750s.

[voxonda]

@ Patrick: Please stay on and share your wealth of experience too. Problem here is that there are sometimes arguments which can only be settled face to face. Problem with forums and e-mails, for that matter, is that is hard to express what people exactly mean. In a 'normal' conversation there are emotions envolved, which can be seen and felt which is not possible thru this medium.

Cheers, Rob

[lordmoonpie]

patrick,

as someone who started his path in this forum some four years ago with wrong foot (and got bashed too) , all i can suggest is that you try and catch first the spirit of the "place". We are not magazine readers reading your amazing personal stories over glossy pages, just simple and mostly poor, (simon LMP aside ) guys who love playing and racing sohc4's. This is one of the best and friendliest forum in the biking world and I've been to a few. so just relax and talk to us on eye level, we care more about valve seat cutting angles than VIP stories.

And welcome to our forum

TG

i don't know tg... honestly... i'm not sure this makes sense to me. i would think a forum should allow as broad a range as possible of content and professional background. i mean, on the face of it, this is in many ways a forum that celebrates history as well as practical and technical topics. it seems to me that well wriiten, detailed in-depth content should have a value here. i don't consider myself a vip at all (although on occasion i've received that treatment as a member of the press and often it kind of bothers me... even if there is a vip sticker on my fiat from having attended the imola 200 revival). but if i were a vip, why should i be made to feel uncomfortable?

maybe this just isn't a good fit. i'm seriously thinking of withdrawing from this whole deal. i've had a very stressful life the last several years and don't need any more angst... especially, through something that has been near and dear to my heart since the age of 14. all the more disappointing, since, by necessity, i had had to set motorcycles aside for several years and felt that now i had time to orient myself back toward that world and that this forum might be a useful part of that process. but maybe i just didn't understand this whole forum business. that's entirely possible. i can certainly direct my energy elsewhere; that's not a problem.

thanks, for the advice just the same.

patrick

Patrick, you should stay around and get familiar with the forum members and forum etiquette. Like most things in life you get out of it what you put in and with the amount of info you *could* put into this forum you *could* get more out of it than most. Your first post was off the mark, for me it disrespected the forum more than the obvious disrespect for Mark and neither was a good first impression. However that aside, it's perfectly possible to have a great time here, talk to some fantastic people and expand your horizons even in cases where you didn't think they could be expanded. On one etiqutte point RR is right - if you want to talk personally to someone then use the PM facility not their email unless invited to through the PM thread.

Personally I'm not a fan of the Daytona bikes for my own ends, I like the earlier stuff, but the history of the whole race scene fascinates me and Daytona is a monumental milestone in that lifecycle. Again personally I don't like the claims around Daniel's bike. For me, provenance is a binary thing - you can either prove it in which case you can claim it, or you can't, in which case you have none. My views though - not borrowed or assumed from anyone. 

So, welcome on board and here's hoping that the experience will start to improve for you as I know it will for us having you contribute and we can all learn and grow together. Hey we can't all be bad - we've taken TG on like a brother 

BTW - Thanks TG, it's true, I'm clever and poor     

[Sam Green Racing]

Rich and thick more like.

Guys, if you don't agree with or disslike a persons post, you have the option of being childish and pressing their ignore button. You can also use the report to moderator function.
I can put up with a bit of thread hyjacking and having a laugh with poor thick Simon but having a go at one another will stop right now, it's my thread, it's my forum and unless you want to find out how nasty I can get, just try me.

Sam, thread starter, forum moderator, MBE OBE CDM.

[lordmoonpie]

Rich and thick more like.

Sam, thread starter, forum moderator, MBE OBE CDM.

I'd settle for Rich and Thick! 

Noted Sam Green,  thread starter, forum moderator, MBE OBE CDM OAP 

[Sam Green Racing]

not far wrong there mate.

[H2Eric]

Noted Sam Green,  thread starter, forum moderator, MBE OBE CDM OAP 

Does that mean 'Many Burgers Eaten', with 'One Boiled Egg' and a 'Cadbury's Dairy Milk, 'Outside A Pub'?

[mick7504]

having a go at one another will stop right now

Right with ya on this one Sam 
It's not a requirement here and that's for sure.
Mick

[napoleonb]

Hi Nap,
I am busy doing the same thing to my CR. I can't help with any part numbers, but have worked it out from pics. when I am a bit further along and have some parts made I will post some pics.

Kevin

With a little bit of help (the original bearing and some additional measurements) I figured out the measurements of the original bushing.
It's not entirely cilindrical on the inside by the way. I am still looking for some good replacement bearings as I have to return the original bearing to its owner but i am very hopefull as I found out that the factory still exists and those bearings are still in production.

[H2Eric]

I purchased this old mag on flea bay recently, as pictures of Dick Mann and the CR750 appear a little thin on the ground I thought I'd share the front cover with y'all.

Cheers
Eric

[Sam Green Racing]

Eric, three shillings and sixpence ya can't buy a bog roll for that these days.

Sam.

[JohnN]

I am a new member who would like to say thank you to all who have provided a wealth of information in this thread. Due to the information regarding CR750's and parts availability I have decided to build a CR750 replica (not a Daytona replica). Please keep the information flowing- I check daily!

I would mike to end my first reply with a question. Are there any guidelines for maximum steering head turn radius to allow clearance to the fairing? It looks like 25-30 degrees (each way) will clear the tank with clip-ons in my preferred position, but a further reduction may be necessary for the fairing. It will not arrive for a few weeks and I want to weld the stops while preparing the suspension and front end. At this time I would rather extend the stops too far since it would be easy to grind them down later.

John

[kmb69]

I know this request has been made more than once over the last couple of years but I gotta ask again. Does any one have good pics or drawings of the factory oil tanks? The MeadSpeed and OverRacing tanks look pretty good but not exactly proper. Pretty please???

Keith

[Sam Green Racing]

I am a new member who would like to say thank you to all who have provided a wealth of information in this thread. Due to the information regarding CR750's and parts availability I have decided to build a CR750 replica (not a Daytona replica). Please keep the information flowing- I check daily!

I would mike to end my first reply with a question. Are there any guidelines for maximum steering head turn radius to allow clearance to the fairing? It looks like 25-30 degrees (each way) will clear the tank with clip-ons in my preferred position, but a further reduction may be necessary for the fairing. It will not arrive for a few weeks and I want to weld the stops while preparing the suspension and front end. At this time I would rather extend the stops too far since it would be easy to grind them down later.

John

Welcome to the forum John, if my memory is anywhere near, I think the stock steering stop on the head stock (steering neck) has to be extended by about quarter of an inch each side.

Sam.

[H2Eric]

Looking at the picture below of Tommy Robb at Daytona 1970 it appears that the fins on the side of the cylinder head have been shaved or made that way so that the width of the head matches that of the cylinder block.



Picture is a bit small (and grainy), but you can download it and blow it up for a better view, gets a bit pixelly though.

The question is, do I have to finally give in and get a pair of specs or was the cylinder head on the Daytona bikes or that available from Honda (12200-300-970) the same width as the cylinder block? Anyone know for sure? Mark (KOS)?

Eric

[Sam Green Racing]

I can't see what you are going on about, your block and head are the same width anyway.

Sam.

[kos]

i have had a couple of the kit CR750 heads in my hands and the were exactly the same size on the outside, the only difference I could see or measure, was that the seats were smaller diameter for the smaller 27mm ex valves and the intake seats were cut larger for the 33.5mm intake valves that the kit head used. I did have a chance one time to have a factory RC works head in my hands and that was very much a smaller casting end to end, as to make the bike narrower. ie: allow the fairing to sit closer to the cylinder head on each side. And it also had what appeared to be a deeper F2 type chamber design!

Now you know....

KOS

[kos]

I know this request has been made more than once over the last couple of years but I gotta ask again. Does any one have good pics or drawings of the factory oil tanks? The MeadSpeed and OverRacing tanks look pretty good but not exactly proper. Pretty please???

Keith

You are correct Keith, OverRacing and MeadSpeed are not correct in their replication. Get a hold of me by PM and I will help you out on your search.

KOS

[Old Scrambler]

John.........you should also consider the mounting tabs for the steering stabilizer when you fit the fairing.........especially if you use the original CR design.

[JohnN]

Thanks Sam and Old Scrambler. I extended the stops 3/8" for now which gives me about 20 degrees each way.

 My steering stem is drilled to accept a stabilizer on the right side, so this will move the pivot point inward slightly which should aid fairing clearance. It also moves the moment arm inward compared to mounting on the tube so perhaps this is not a good idea. I'll let it go until next month when when the fairing arrives and check clearances then.

[H2Eric]

i have had a couple of the kit CR750 heads in my hands and the were exactly the same size on the outside, the only difference I could see or measure, was that the seats were smaller diameter for the smaller 27mm ex valves and the intake seats were cut larger for the 33.5mm intake valves that the kit head used. I did have a chance one time to have a factory RC works head in my hands and that was very much a smaller casting end to end, as to make the bike narrower. ie: allow the fairing to sit closer to the cylinder head on each side. And it also had what appeared to be a deeper F2 type chamber design!

Now you know....

KOS

Thanks Mark you're a star. The good news is that my eyes were not deceiving me and I can put off wearing specs a bit longer!

Eric

[kmb69]

I know this request has been made more than once over the last couple of years but I gotta ask again. Does any one have good pics or drawings of the factory oil tanks? The MeadSpeed and OverRacing tanks look pretty good but not exactly proper. Pretty please???

Keith

You are correct Keith, OverRacing and MeadSpeed are not correct in their replication. Get a hold of me by PM and I will help you out on your search.

KOS

PM Sent.

[voxonda]

@H2Eric,

Will upload a pic of the '73 Sumiya works 750 which shows the 'slim' cylinderhead very well.

Rob

[voxonda]

Here it is:


Cheers, Rob

[H2Eric]

@H2Eric,

Will upload a pic of the '73 Sumiya works 750 which shows the 'slim' cylinderhead very well.

Rob

Thanks Rob, much appreciated.

Regards
Eric

[Sam Green Racing]

For Gods sake Eric, don't let Mike know that you shaved his block down just to fit your fairing.

Sam.