Increasing Bore Size
- Thread starter Rkm85
- Start date
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Is there a specific reason you want to bump up the bore size? Are the sleeves damaged? How original is the rest of the motorcycle?
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There's two ways to do this.
The expensive way. This is an upgrade my bike has. New ten-stud cylinder head, barrels, conrods, pistons. So, a 'proper' 750 top end.
Less expensive way. A 750 conversion kit. Keep existing conrods and cylinder head Takes standard pistons, which is good.
My bike was already converted on purchase, so can't state experienced difference. I know people are happy with the extra torque the upgrades give.
Triumph introduced a ten-stud head for a reason when boring out bikes to 750cc.
Do you feel limited with the torque you have? Or is it the grass is greener thinking? If you like spending money upgrading your bike, probably will give satisfaction?
The expensive way. This is an upgrade my bike has. New ten-stud cylinder head, barrels, conrods, pistons. So, a 'proper' 750 top end.
Less expensive way. A 750 conversion kit. Keep existing conrods and cylinder head Takes standard pistons, which is good.
My bike was already converted on purchase, so can't state experienced difference. I know people are happy with the extra torque the upgrades give.
Triumph introduced a ten-stud head for a reason when boring out bikes to 750cc.
Do you feel limited with the torque you have? Or is it the grass is greener thinking? If you like spending money upgrading your bike, probably will give satisfaction?
Thanks for the info. It probably a mix between wanting more torque and the grass being greener. I have seen the conversion kits and wondered about the head pressures.
I've read lots of threads where people are happy with the conversion kit. Helps two up riding.
Not read any problems with the extra pressure on the single centre stud, rather than two centre studs Triumph used for 750s. But Triumph did see fit to use ten studs.
speedrattle
Well-Known Member
ive run a morgo 744 kit on my 72 T120 for three decades. very pleased.
the T140 swap requires you to finesse the heady steadies and maybe exhsust pipes, as the short rod T140 is 1/2 inch shorter. a 750 kit is a direct bolt on and the long rod motor works well.
without cam ir head work you wont see a lot of top end difference but there will be more bottom and midrange.
my morgo has over thirty years on it now and cold compression is only 150 psi, but it still does 118 at the land speed races.
both aerco and morgo make 9-bolt kits
the T140 swap requires you to finesse the heady steadies and maybe exhsust pipes, as the short rod T140 is 1/2 inch shorter. a 750 kit is a direct bolt on and the long rod motor works well.
without cam ir head work you wont see a lot of top end difference but there will be more bottom and midrange.
my morgo has over thirty years on it now and cold compression is only 150 psi, but it still does 118 at the land speed races.
both aerco and morgo make 9-bolt kits
