allow me to introduce the reason I am frequenting your rather excellent forum - project XR11/73. This is being built in response to a challenge on another 2-stroke forum, the rules of which are fairly simple - build a project bike using an engine and frame combo that aren't made for each other. My entry into this challenge is a GT750-powered, GSXR400 (GK73A)-framed track day bike which will have visual connections to the early TR750 racers - namely the blue/white paint scheme, gold wheels, TR seat unit, forward-facing calipers etc.
With the acquisition of a GK73A frame today, I now have a near-complete rolling chassis to complement the GT750J motor I bought from DK a while back.Shame they aren't compatible..........
So first job is to get the behemoth of a motor to snuggle into the lovely alloy beam frame. The rear mounts on the Kettle motor measure 16.5mm across (with the rubbers in place) - the cast-in frame lugs are 14mm apart. So thats the first (of many) obstacles I will have to overcome.
Pictures to follow.....................
XR11/73
- yeadon_m
- Posts: 7401
- Joined: Sat Jan 02, 2010 7:10 am
- Location: Canterbury Kent
Re: XR11/73
Welcome Garry!
I am 'a standard man' myself so I don't know anything about converting bikes...however, on another forum there clearly is expertise:
http://www.suzuki2strokes.com/forum/vie ... 4&start=15
Looking forward to progress on anything with a GT motor in it :-))
Cheers,
Mike
I am 'a standard man' myself so I don't know anything about converting bikes...however, on another forum there clearly is expertise:
http://www.suzuki2strokes.com/forum/vie ... 4&start=15
Looking forward to progress on anything with a GT motor in it :-))
Cheers,
Mike
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
some pictures - saves a thousand words.............
first trial fit of GT750 motor in GSXR400 frame - the front mounts
and the upper rear mounts
my solution - make new mounts and attach in-line with existing mounts, but spaced much wider
the front mounts had to go..............
that allows the motor to sit a lot higher in the frame
I was about to take the frame for welding of the new rear upper brackets when I realised I could move the motor further back to give more clearance for the headers, so......................
first trial fit of GT750 motor in GSXR400 frame - the front mounts
and the upper rear mounts
my solution - make new mounts and attach in-line with existing mounts, but spaced much wider
the front mounts had to go..............
that allows the motor to sit a lot higher in the frame
I was about to take the frame for welding of the new rear upper brackets when I realised I could move the motor further back to give more clearance for the headers, so......................
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
............so, time to fire up the grinder again and remove some more metal - this time, all the rear motor mounts
the frame, de-mounted
fitting the swingarm allowed me to shift the motor as far back in the frame as the swingarm pivot would allow - I shimmed it at 2mm from the pivot and 2mm below the cross-piece and it starts to look promising...........
next step is to fabricate some new rear upper motor mounts and clean the frame where the original mounts once were
the frame, de-mounted
fitting the swingarm allowed me to shift the motor as far back in the frame as the swingarm pivot would allow - I shimmed it at 2mm from the pivot and 2mm below the cross-piece and it starts to look promising...........
next step is to fabricate some new rear upper motor mounts and clean the frame where the original mounts once were
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- Rhencullen
- Posts: 715
- Joined: Tue Dec 13, 2011 7:10 pm
- Location: Lincolnshire
Re: XR11/73
Will the engine 'stiffen' and form part of the frame, like my 900R then Garry ?
1977 Suzuki GT750B - 2003 Honda CB1300 - 1979 Honda CBX1000
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
Indeed it will. Current thinking is to "hang" the motor via the cylinder head, like the Drysdale kit for RG500's.
I really don't want a cradle as it will spoil the illusion of the engine hanging unsuspended from the frame.
I really don't want a cradle as it will spoil the illusion of the engine hanging unsuspended from the frame.
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
when space is at a premium, every little helps. This casting on the back of the Kettle gearbox is what I used to shim the motor away from the swingarm pivot - it's approx 3mm wide -
but not anymore.............
:D
but not anymore.............
:D
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
A few pics of the new rear upper engine mounts..............
time to visit my welders..................
time to visit my welders..................
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- garry55
- Posts: 306
- Joined: Fri Dec 27, 2013 2:49 pm
- Location: White Rose County
Re: XR11/73
To pass time, and move the project forwards, I have spent part of my last 2 night shifts at work grinding-off the remains of the front engine mounting castings and weld to tidy the frame. A bit of filing and rubbing with emery cloth and it will be a lot neater. And lighter ! :D
Look away now if you are of a nervous disposition - to clear the new rear motor mounts, I had to relieve some more surplus metal from the Kettle motor. Who needs an oil pump cover anyway? :wink:
Look away now if you are of a nervous disposition - to clear the new rear motor mounts, I had to relieve some more surplus metal from the Kettle motor. Who needs an oil pump cover anyway? :wink:
Garry.
Inside every standard Kettle is a bloody good engine crying for help...............
Inside every standard Kettle is a bloody good engine crying for help...............
- Rhencullen
- Posts: 715
- Joined: Tue Dec 13, 2011 7:10 pm
- Location: Lincolnshire
Re: XR11/73
You're certainly making good use of that grinder / cutting wheel Garry :-)
1977 Suzuki GT750B - 2003 Honda CB1300 - 1979 Honda CBX1000