Honda CB 450 T

**Mr Merde** · 15th April 2007, 22:14

I putn the word around that I was after an engine for a bike that I could build into a straight liner, a 1/4 mile special.

I have the possibility of getting an old CB450 T that is still running but in tatty condition cosmetically.

What I want to know is if anyone out there has any experience with tuning these engines. Can they be made to scream? I know they reved out to about 10,000 rpm and stock they put out 45-50 hp.

Has any one here ever pushed it higher.

The bike comes complete so I will have the frame to play around with.

This is a longish term project, but I would like to be able to give it a run when the next season of drag racing starts.

So you people in the know, please be forthcomming.

Advice please.

Mr

**jonbuoy** · 15th April 2007, 23:02

http://www.motorcycle.com/mo/mctext/h_hon.html Not sure if this is the same era as the motor you have

**Paul in NZ** · 16th April 2007, 08:43

Thats odd - I've 'obtained' a dead (ish) CB450 me self... for a project... I assume you mean the old DOHC CB450 and not the later SOHC 400?

Research thus far tells me that the CB450's were / are used in the USA as pretty fair classic road racers BUT that a hell of a lot of frame modification is required to get them to handle (which would fit with my memory of my flatmates one when they were new). Engines are expensive to fix if shagged and a lack of oil filter means they are often shagged. The recommendation I have thus far is to strip the engine and see if the crank is OK and if it is - procede.

Cheers

**Mr Merde** · 16th April 2007, 09:35

Originally Posted by Paul in NZ

Thats odd - I've 'obtained' a dead (ish) CB450 me self... for a project... I assume you mean the old DOHC CB450 and not the later SOHC 400?

Research thus far tells me that the CB450's were / are used in the USA as pretty fair classic road racers BUT that a hell of a lot of frame modification is required to get them to handle (which would fit with my memory of my flatmates one when they were new). Engines are expensive to fix if shagged and a lack of oil filter means they are often shagged. The recommendation I have thus far is to strip the engine and see if the crank is OK and if it is - procede.

Cheers

Thats correct as far as I know so far. The bike is really rough but is running. I'm not really looking for handling as I only plan in travelling for 1/4 mile in a straight line. Possibly turning around at the end of it and then travelling down the pit lane to get ready to do it again.

Was pointed to a site in the previous post where they worked on one of these machines. Changed the heads for one from a 500T. How rare are these beasts in NZ

The whole page looks good.

Gives me ideas of where to go.

My aim was for an engine that pumped out a lot of torque. A single would have done this but probably may have lacked at the later part of the 1/4 mile. A 4 cylinder would have the back end power but loose out somewhat at the start.

Compromise. A 2 cylinder.

The class I'm hoping to compete in is from 0-499cc. So I think this engine fits the bill quite nicely. even a little freeway to overbore if needed.

**Big Dave** · 16th April 2007, 09:43

Originally Posted by Mr Merde

Advice please.

Mr

Madness.
What was the objective? - find the most unsuitable engine you can?
Pushing Merde up hill with a pointy stick. ;-P

**Paul in NZ** · 16th April 2007, 10:02

Originally Posted by Big Dave

Madness.
What was the objective? - find the most unsuitable engine you can?
Pushing Merde up hill with a pointy stick. ;-P

Why unsuitable? (no really - I need to know before I get the spanners out myself) The CB450 is old and heavy but people have got pretty respectable power out of them in the classic racing world?

**Mr Merde** · 16th April 2007, 10:06

Originally Posted by Big Dave

Madness.
What was the objective? - find the most unsuitable engine you can?
Pushing Merde up hill with a pointy stick. ;-P

Find any engine I can play with. I know what class I want to enter now to find an engine that fits into this class. If you can suggest a better alternative I would be most appreciative.

Lots of torque at start with enough power to be still pulling at the end of the 1/4 mile.

From what I have seen the national record for this class is something like 11.3 seconds. That must be able to be bettered.

Budget dictates what can be used.

This bike and engine were free and this works fine by me.

I like the "pushing" line.

**Paul in NZ** · 16th April 2007, 10:49

Originally Posted by Mr Merde

Find any engine I can play with. I know what class I want to enter now to find an engine that fits into this class. If you can suggest a better alternative I would be most appreciative.

Lots of torque at start with enough power to be still pulling at the end of the 1/4 mile.

From what I have seen the national record for this class is something like 11.3 seconds. That must be able to be bettered.

Budget dictates what can be used.

This bike and engine were free and this works fine by me.

I like the "pushing" line.

Big 500 class two stroke MX bike should do the trick I'd have thought?

**Logan5** · 16th April 2007, 19:08

It's no good for telling you how to make them scream, but I have in my posession one Clymer Publications Honda Service Repair Manual All 450 Models 1965-1973. Free to a good home. Interested?

**Paul in NZ** · 16th April 2007, 19:53

Shit yes....

**SPman** · 17th April 2007, 13:57

Have a mate in Waitara who knows a bit about 450 twins - he's restored a K4 & a Black Bomber and has mates who race these things. (he's currently trying to collect/restore, one of every model Honda made in the 60's...

) I'll dig his Email addy out when I get home, if ya like

**Paul in NZ** · 17th April 2007, 14:04

Originally Posted by SPman

Have a mate in Waitara who knows a bit about 450 twins - he's restored a K4 & a Black Bomber and has mates who race these things. (he's currently trying to collect/restore, one of every model Honda made in the 60's...

) I'll dig his Email addy out when I get home, if ya like

That would be great.. Thanks

**Mr Merde** · 17th April 2007, 14:28

Originally Posted by SPman

Have a mate in Waitara who knows a bit about 450 twins - he's restored a K4 & a Black Bomber and has mates who race these things. (he's currently trying to collect/restore, one of every model Honda made in the 60's...

) I'll dig his Email addy out when I get home, if ya like

I would appreciatew it also. Thanks

**Big Dave** · 17th April 2007, 14:31

'The CB450 is old and heavy'

My first road going motorcycle.
I remember how it went very well. Madness.

Power to weight.
And there was something else that they did - don't remember - but most of them died the same death - conrods?? or a valve - nah, gone.

I had a SR500 after that was a whole lot more fun.

**Mr Merde** · 17th April 2007, 14:45

Originally Posted by Big Dave

'The CB450 is old and heavy'

My first road going motorcycle.
I remember how it went very well. Madness.

Power to weight.
And there was something else that they did - don't remember - but most of them died the same death - conrods?? or a valve - nah, gone.

I had a SR500 after that was a whole lot more fun.

Know of any going for sale anywhere then?

I am getting what I wanted from this thread,

information and ideas.