atom3624
Well-Known Member
..... with the FG MT 'Blue Thunder'.
It's been snapping the RHS long bolt that screws through the side brace into the pullstart, and also the alloy bracing bushing.
I did have a few of these, so I'm OK there, but each time I need to remove the rear RHS, the side bracing and sometimes I loosen the 4 lower engine bolts.
After the second time the bolt snapped - stub is easily removed once the pullstart is removed - I looked a bit further.
Reason for the snapping is the engine was moving as the upper, rear brace bolt .... was missing!!
Once re-assembled, I went out again, and it was flying, but jammed ... damn!!
Cabin Fever with all of this cold weather keeping me inside hadn't done any favours!!
I hadn't re-tightened the lower 4 engine bolts - duhh!!
I'd been running 50/14 spur/pinion gearing for the larger MCD tyres - TBH they're wider, but the overall circumference isn't any different.
As I have a Trevor Simpson 2-bolt 28.5cc reed valve in it, I thought I'd try out the Marder 44/20 gears on it ....
Ended up WAY too tall and wasn't really getting into the power band and just beyond 'bogging'.
Each time I've replaced the coupling tubing.
I run a piece of the 1-metre length of 'high temperature oil/fuel resistant silicone tubing', but the inside seems to .... thermally decompose after perhaps 1-2 hours' running.
I had some thick rubber Chinese couplings to try, with moulded recesses for the jubilee clips.
I returned to the 'MT standard' 48/16t spur/pinion - again steel - I had 'in the box' and out it came again. Engine spools up nicely, wheelies just about possible despite the weight, then the volume went from 4-7 !!!
This was after less than 10 minutes and could mean only one thing - the coupling was stuffed - sure enough!!
I've re-aligned the exhaust, and replaced with another piece of the silicone tubing and after the first run, all is good.
All bolts are tight now!!!
Al.
It's been snapping the RHS long bolt that screws through the side brace into the pullstart, and also the alloy bracing bushing.
I did have a few of these, so I'm OK there, but each time I need to remove the rear RHS, the side bracing and sometimes I loosen the 4 lower engine bolts.
After the second time the bolt snapped - stub is easily removed once the pullstart is removed - I looked a bit further.
Reason for the snapping is the engine was moving as the upper, rear brace bolt .... was missing!!
Once re-assembled, I went out again, and it was flying, but jammed ... damn!!
Cabin Fever with all of this cold weather keeping me inside hadn't done any favours!!
I hadn't re-tightened the lower 4 engine bolts - duhh!!
I'd been running 50/14 spur/pinion gearing for the larger MCD tyres - TBH they're wider, but the overall circumference isn't any different.
As I have a Trevor Simpson 2-bolt 28.5cc reed valve in it, I thought I'd try out the Marder 44/20 gears on it ....
Ended up WAY too tall and wasn't really getting into the power band and just beyond 'bogging'.
Each time I've replaced the coupling tubing.
I run a piece of the 1-metre length of 'high temperature oil/fuel resistant silicone tubing', but the inside seems to .... thermally decompose after perhaps 1-2 hours' running.
I had some thick rubber Chinese couplings to try, with moulded recesses for the jubilee clips.
I returned to the 'MT standard' 48/16t spur/pinion - again steel - I had 'in the box' and out it came again. Engine spools up nicely, wheelies just about possible despite the weight, then the volume went from 4-7 !!!
This was after less than 10 minutes and could mean only one thing - the coupling was stuffed - sure enough!!
I've re-aligned the exhaust, and replaced with another piece of the silicone tubing and after the first run, all is good.
All bolts are tight now!!!
Al.
