Topic: 1978 CB750 Cafe conversion Front end [re-assembly]

[Rnobx67]

Hi Guys,

Finally get my base CB750, didn't want to cut or modify an 69-76, so I opted for a big tank 78 CB for affordable price. Running need synchro, but all is there.

a small tour :

Before by RnOw, sur Flickr






My shop found a Front end from a ZX6R... will see what'shappen so.



I'm going into a cafe racer project, clean as I can.

[Rnobx67]

My first Question I dont know if I keep the regular color for the Triple tree or I go on black satin on that textured triple tree

[SOHC4 Cafe Racer Fan]

Color is really up to YOU.  The bigger question is whether you are going to stick with the smaller offset of the ZX6R triple trees or get a new set of triple trees to restore the offset to stock geometry.  If you go with the smaller offset, the front will not be as stable in corners.

If you decide to get custom offset triples, Devin at Cognito Moto can make them if you send you ZX6R triples to him.  He can also CNC you a front wheel hub that will fit the ZX brake rotors and allow spoked wheels.  Just a thought on ways to spend your $$.

[Rnobx67]

I know I managed to have triple tree machined next, but for now I will use those from the ZX6R.

If it's really to tricky, than I will change it as soon as I can.

And for now also I have to choose new boots, here in Canada the BT45 are so much expensive ! And 78's are 130 wide large at rear, is the Spitfire a good choice ?

[Rnobx67]

What are other options ?

[SOHC4 Cafe Racer Fan]

I have to agree with Cal.  Spitfires have limited grip.  BT-45s are much better.  Another option to consider is Avon Roadrider tires.

[Rnobx67]

Ok, my garage propose me Roadrunners too, and Shinko Kruz too but I've never heard of it ...

[SOHC4 Cafe Racer Fan]

Why put a ZX front end on a vintage motorcycle than handicap that bike with crappy, cheap tires? Avons, Pirelli Sport Demons, BT-45s at least.

i
+1

[Rnobx67]

I'm totally ok with you, all I want is the best but he is announce me a price at 240$ for the back, I was aware for a price at 140... 70% more

I want the best but not at a insane price, I want buy at the real price.

If I buy it online that's fair for me. I just want buying with my local shop

[Rnobx67]

I've read for now By positives orders of comments  :
Bridgestone Battlax BT-45 (+)(+)(+)
Pirelli Sport Demons (+)
Avon Roadrunner (+)
Metzeller Lasertec (+)(-)

Hors serie :
Dunlop K81 TT100 (+)(+)(+)

[754]

There is a place in or near Montreal has really good online bike tire prices.

[754]

Petes Superbike in PQ has 120/70H  BT45 for 123.00
Your dealer seems a bit high.

[Rnobx67]

Ok, for tires... I order them online...

[Rnobx67]

Finally I got my tires at Pete Superbikes, brand new BT45  <3
My mech have done all work, but finally my nightmare was coming from the seat maker, a return and 2 month for having it back...
fork swap was done, powdercoat one triple tree too

[SKTP]

looking good

[Rnobx67]

The blank mount


then...

[Rnobx67]

looking good

I will love to do the same tank as yours, black and gold (without the red

[SOHC4 Cafe Racer Fan]

Photo Bucket strikes again! 

[Rnobx67]

Photo Bucket strikes again! 

Shii doesn't work anymore this site ?

[Rnobx67]

So today I on my quest for finding 5x25mm fuses.... Oh my ! It's unavailable at all places I were... I order on vintage CB750, but unfurtunatly can't be delivered by FedEx, working hours only week, please ... nothing on amazon, Edison, Canadian Tire... I'm tired

[Rnobx67]

Hi guys I'm going forward with my bike. I strip down everything i could till now, figuring how to remove motor from frame... My lift let me down...

How can I put photos now ? till can't with photobucket !

Also I'm drawing my own triple tree and I will be able do make milling it by a guy nearby, maybe a little overpriced but...

I've some question about the bottom triple till I didn't remove it from bike till now. What's the diameter of the stem, and there is a ball bearing, so before removing these if I can have some advice or information.

[SOHC4 Cafe Racer Fan]

Hi guys I'm going forward with my bike. I strip down everything i could till now, figuring how to remove motor from frame... My lift let me down...

How can I put photos now ? till can't with photobucket !

Also I'm drawing my own triple tree and I will be able do make milling it by a guy nearby, maybe a little overpriced but...

I've some question about the bottom triple till I didn't remove it from bike till now. What's the diameter of the stem, and there is a ball bearing, so before removing these if I can have some advice or information.

I am not sure what your machinist wants to charge you, but you will want to increase the offset between the steering stem and the forks closer to the stock offset.  If the combined cost of replacing the stem and triples approaches the range of $500, you should simply have Devin at Cognitomoto make them for you.

[Rnobx67]

Hi guys I'm going forward with my bike. I strip down everything i could till now, figuring how to remove motor from frame... My lift let me down...

How can I put photos now ? till can't with photobucket !

Also I'm drawing my own triple tree and I will be able do make milling it by a guy nearby, maybe a little overpriced but...

I've some question about the bottom triple till I didn't remove it from bike till now. What's the diameter of the stem, and there is a ball bearing, so before removing these if I can have some advice or information.

I am not sure what your machinist wants to charge you, but you will want to increase the offset between the steering stem and the forks closer to the stock offset.  If the combined cost of replacing the stem and triples approaches the range of $500, you should simply have Devin at Cognitomoto make them for you.

Yeah I want to increase the offset, it's really pain in the ass at low speed/foot to handle the bike.
It would be simple as this, but I have a ZX6R fork now, and Devin charge same price as the machinist, so I want to do mine
I already done some drawings so it's my job too and I will be very proud to do have my own pieces

CAD_top_tree by RnOw, sur Flickr

CAD_down_tree by RnOw, sur Flickr

CAD_drawing by RnOw, sur Flickr


But for now I'm just there :
demontage001 by RnOw, sur Flickr

need to pull off the motor and it will be better to remove front end

[Rnobx67]

You remove the stock CB ball bearings by simply pulling the the stem out of the neck, and they will fall all over the workshop floor.

If you are referring to the GSXR bearings installed on the stem, the easy way is to toss the lower triple into the freezer overnight. Then tomorrow after work, pop out to the shop, a quick but careful tap with a cold chisel between the bearing race and lower tree, and it will come sliding off.

like on old bicyles headset and bottom brackets... Dont, know what my mech have put on the last conversion, so it's a BB from CB or ZX6R, I will see...

[SOHC4 Cafe Racer Fan]

If you are going to pull the motor, and it is clear you are not doing a concourse restoration, I'd recommend that you install a frame kit (see member 754 aka Frank who has a weldless kit).  This will allow you (after installation) to service the entire top end of the motor in the frame.  So if you have any latent oil leak in the top end, you can easily work on it and not have to pull the entire motor. 

I always thought it would not be necessary, because I never thought I'd pull the motor more than once.  3 times later, I installed the frame kit.