XR11/73

[Suzukidave]

Yep .. the dry clutch setup looks trick for sure

[old racer]

well - still waiting for the cylinder head modifications to be completed - but after a lengthy chat with a UK engineering company, I purchased one of these.............



its a 3mm barrel spacer that, when fitted, replicates the works Suzuki TR750 race bikes porting, without having to carve the ports open. Neat eh ?

Will have to skim the barrel top surface to suit, modify the pistons skirts and remove some material from the head to get the correct compression ratio, but with a set of suitable spannies I should be getting 80+ bhp at the rear wheel. That'll do for starters.....

Something wrong with those figuers Garry,The suzuki TR750 put out around 120BHP.

[tz375]

well - still waiting for the cylinder head modifications to be completed - but after a lengthy chat with a UK engineering company, I purchased one of these.............



its a 3mm barrel spacer that, when fitted, replicates the works Suzuki TR750 race bikes porting, without having to carve the ports open. Neat eh ?

Will have to skim the barrel top surface to suit, modify the pistons skirts and remove some material from the head to get the correct compression ratio, but with a set of suitable spannies I should be getting 80+ bhp at the rear wheel. That'll do for starters.....

Something wrong with those figures Garry,The Suzuki TR750 put out around 120BHP.

Not too many of them though and not at the rear wheel. To your point though, the difference between a TR750 and GT750 exhaust port is around 10.5mm on a JKL and 8mm on a MAB.

A 3mm spacer takes port timing from really soft to slightly sporty and still nowhere near say an RD350 Yamaha let alone a TR. These fat old ladies are not exactly sporty. There is a long way you can go - if you are careful and know what you're doing.

At about 100 HP you are looking at an O ring head and at 120 a new clutch and so on.

[old racer]

I have never had a problem with the cyl heads.
In later years i did run them with the steel factory head gaskets.

[garry55]

BDK can get around 110bhp at the rear wheel of their GT750-based sidecar outfit. I'm looking to get around 80 as a starter - I want reliability plus I need to know the chassis can cope with that amount of power before upping it. I do have a GSX-R600 chassis waiting in the wings.........

100+bhp comes at great expense if you can't do your own machining - which I can't - so I'm not sure I want to venture that far.

[Suzukidave]

If you should decide to go with the 600 frame it would be interesting to see what different means you go with to get the engine in .

[Suzukidave]

Any thing new to tell Gerry

[garry55]

still waiting for the cylinder head work to be completed Dave - turnaround was 2 weeks - now into the 9th week

But I have been very busy with my Tesi racer project, so no idle time.

[Suzukidave]

Do you have a site you are showing your Tesi work as that would be very interesting seeing progress on a rare bike like that too

[garry55]

http://www.bimotaforum.co.uk/viewtopic.php?t=1558" onclick="window.open(this.href);return false;

if you have an hour to spare……….

[Suzukidave]

Very nice build thread

[garry55]

why thankyou, Sir...........

wish it was finished.

[Suzukidave]

why thankyou, Sir...........

wish it was finished.

Oh yeah , a wonderful project and great determination to revive such a rare bike

[rngdng]

I noticed that your water-pump drive gear is cracked. I haven't posted this repair in a while, maybe someone can use it.


http://www.3cyl.com/rngdng/Gear_repair.pdf


Lane

[oldjapanesebikes]

I noticed that your water-pump drive gear is cracked. I haven't posted this repair in a while, maybe someone can use it.

Lane - that is a useful tip, but would you not agree it is best to just buy a new one ? They are still available directly from Suzuki dealers everywhere on the planet other than the USA eh ?