Old Bob's Blog Stuff
Older Bob's Blog Stuff
Even Older Bob's Blog Stuff
07/06/2011
The SLR head came back from SEP with new exhuast valve guides, spark eroded exhaust stud and two repaired cam cover holes - £92 all in, bargain!
It took about 5 hours to put the bike back together and it was pressed into service
It's very satisfying to ride a bike you rebuilt yourself - every mile is a victory :o)
The FX650 got dropped on a trail, which smashed the headlight fairing, front mudguard, indicators etc. Now it looks like this
Which is more like it to my eyes..
I went to the drag racing at Santa Pod, third time I've been and the impact is never any less, I have NEVER seen anything like those top fuel rails. 0 to 330MPH in 4.4 seconds...
Here's a 1000HP bike in the pits.
On the run down and back (2 hours each way) I was getting some wrist pain in the right arm, from hanging onto an unfaired bike in the headwind. With a trip to France coming up I had to think of a solution - cruise control!
I made a slug that fits inside the bar end (held in with two M5 screws) and the other bit is a quick release skewer from a push-bike wheel spindle. The skewer screws into the slug, then there's a thin aluminium disc that bears onto the plastic end of the twist grip. It works a treat, it's a friction brake as opposed to a lock so you can turn the throttle easily when the lock is on.
24/03/2011
I've looked at the spring for the decompressor and it should definately be there. I wasn't sure about taking the whole thing apart again, but then it started smoking from cold and on the over-run. Valve stem seals are a common problem on these so two birds with one stone philosophy dictated I get on with it.
The bike is very easy to work on, one pot, no water cooling etc. It took about an hour to get the head off
Here you can see the radial valve arrangement that gives the engine it's "RFVC" name. In most engines the exhaust valves would be parallel to each other and the inlet valves would be parallel too. Here all four valves enter the combustion chamber at an angle.
The piston in the bike is 100mm diameter, it's a heck of a size
I stripped the valves out of the head and the fault was immediately apparent
Both the exhaust stem seals were fitted incorrectly, the steel band that should go round the base of the seals were actually floating about on the valve guide below the seal. Also here you can see the exhaust stud that snapped during the removal of the exhaust.
Looking from the bottom you can see that the right hand exhaust seal (on the left in the photo) was the one that was leaking, producing a sooty wet build up at the bottom of the valve guide.
It also turns out the valve guides are shot, so the head will go to SEP in Kegworth, they will fit new exhaust valve guides and spark erode the snapped stud out. I tried drilling it with HSS, HSS/titatium and tungsten drill bits and nothing touched it - what the hell are those studs made of?
I'm not off the road because I picked up a bargain FX650 vigor (same as the SLR but newer) at the weekend :o)
05/03/2011
The SLR is back together, the new decompressor rattles less than the old one, but it still rattles. Looking at an exploded diagram there may be a spring involved, which isn't present in my engine. Now I'm not going to start bunging springs in my camshaft if I'm not certain it should be there, so I'll take the cam out of my spare engine and see if that has a spring.
The bike runs well and after a week of forced on-road riding (because I've been running the outfit) I took the SLR out this morning for a spot of green lane riding.
This trail is quite hard going, more like a rocky stream than a green lane. Still, it was good to get out in the mud. I tend to go either very early (these photos were taken at 7:30AM) or at night, to avoid conflicts with walkers who will insist on shouting at you even though you're not doing anything wrong - guess they just want everything their own way...
02/03/2011
The SLR is going really well, it's a punchy number and is great fun to ride, but it makes an annoying noise at about 3000RPM. It's a metallic jingling rather than a rattle and it's only at a certain RPM. Internet research pointed to the decompressor being the culprit. There was nothing for it but to go in for a look.
Everything went OK except for two snapped studs at the front of the cam cover, they've seized because the bottom of the thread is open to the elements (nice design Honda), I'm hoping to get away with leaving them out as they're not at the edge and there are 10 other studs holding the thing down.
The sprocket carrier is pressed onto the cam and needed heat and some "persuasion" to remove
The cam looks OK, maybe the tappets have been run a bit tight as there's some evidence of heat discolouration on the lobes. The decompressor is the bit that's a different colour on the right hand end.
Here I've moved the decompressor from it's locating pin, it's a loose fit over the cam and this pin and it seems designed to rattle - I can't fathom how it wouldn't rattle!
I've ordered a new one anyway (they're only cheap) and at the same time I've ordered new camshaft bearings.
The one on the left is a standard part, but the right hand one is a Honda special (typical Honda).
There's a weeks wait for the parts and it'll go back together easy enough and if it wants to rattle then it'll have to just rattle.
You might be detecting a little "anti Honda bias" here and you'd be right - I really don't like Hondas, except for C90, CG125 and any single with the RFVC head, which started out with the excellent XBR500.
In the meantime the trusty GS750 has been pressed into service
I had another HT coil go last month, but it's back on form now. After 3 years of outfit riding I'm finally getting confident enough to really start enjoying the ride now, locking up wheels, lifting the chair, spinning the back tyre etc..
A bit of welding and grinding and I've produced this:
This is Bob's patent custom made SLR650 Rifle carrier, more on that later....
Older Bob's Blog Stuff
Even Older Bob's Blog Stuff
07/06/2011
The SLR head came back from SEP with new exhuast valve guides, spark eroded exhaust stud and two repaired cam cover holes - £92 all in, bargain!
It took about 5 hours to put the bike back together and it was pressed into service
It's very satisfying to ride a bike you rebuilt yourself - every mile is a victory :o)
The FX650 got dropped on a trail, which smashed the headlight fairing, front mudguard, indicators etc. Now it looks like this
Which is more like it to my eyes..
I went to the drag racing at Santa Pod, third time I've been and the impact is never any less, I have NEVER seen anything like those top fuel rails. 0 to 330MPH in 4.4 seconds...
Here's a 1000HP bike in the pits.
On the run down and back (2 hours each way) I was getting some wrist pain in the right arm, from hanging onto an unfaired bike in the headwind. With a trip to France coming up I had to think of a solution - cruise control!
I made a slug that fits inside the bar end (held in with two M5 screws) and the other bit is a quick release skewer from a push-bike wheel spindle. The skewer screws into the slug, then there's a thin aluminium disc that bears onto the plastic end of the twist grip. It works a treat, it's a friction brake as opposed to a lock so you can turn the throttle easily when the lock is on.
24/03/2011
I've looked at the spring for the decompressor and it should definately be there. I wasn't sure about taking the whole thing apart again, but then it started smoking from cold and on the over-run. Valve stem seals are a common problem on these so two birds with one stone philosophy dictated I get on with it.
The bike is very easy to work on, one pot, no water cooling etc. It took about an hour to get the head off
Here you can see the radial valve arrangement that gives the engine it's "RFVC" name. In most engines the exhaust valves would be parallel to each other and the inlet valves would be parallel too. Here all four valves enter the combustion chamber at an angle.
The piston in the bike is 100mm diameter, it's a heck of a size
I stripped the valves out of the head and the fault was immediately apparent
Both the exhaust stem seals were fitted incorrectly, the steel band that should go round the base of the seals were actually floating about on the valve guide below the seal. Also here you can see the exhaust stud that snapped during the removal of the exhaust.
Looking from the bottom you can see that the right hand exhaust seal (on the left in the photo) was the one that was leaking, producing a sooty wet build up at the bottom of the valve guide.
It also turns out the valve guides are shot, so the head will go to SEP in Kegworth, they will fit new exhaust valve guides and spark erode the snapped stud out. I tried drilling it with HSS, HSS/titatium and tungsten drill bits and nothing touched it - what the hell are those studs made of?
I'm not off the road because I picked up a bargain FX650 vigor (same as the SLR but newer) at the weekend :o)
05/03/2011
The SLR is back together, the new decompressor rattles less than the old one, but it still rattles. Looking at an exploded diagram there may be a spring involved, which isn't present in my engine. Now I'm not going to start bunging springs in my camshaft if I'm not certain it should be there, so I'll take the cam out of my spare engine and see if that has a spring.
The bike runs well and after a week of forced on-road riding (because I've been running the outfit) I took the SLR out this morning for a spot of green lane riding.
This trail is quite hard going, more like a rocky stream than a green lane. Still, it was good to get out in the mud. I tend to go either very early (these photos were taken at 7:30AM) or at night, to avoid conflicts with walkers who will insist on shouting at you even though you're not doing anything wrong - guess they just want everything their own way...
02/03/2011
The SLR is going really well, it's a punchy number and is great fun to ride, but it makes an annoying noise at about 3000RPM. It's a metallic jingling rather than a rattle and it's only at a certain RPM. Internet research pointed to the decompressor being the culprit. There was nothing for it but to go in for a look.
Everything went OK except for two snapped studs at the front of the cam cover, they've seized because the bottom of the thread is open to the elements (nice design Honda), I'm hoping to get away with leaving them out as they're not at the edge and there are 10 other studs holding the thing down.
The sprocket carrier is pressed onto the cam and needed heat and some "persuasion" to remove
The cam looks OK, maybe the tappets have been run a bit tight as there's some evidence of heat discolouration on the lobes. The decompressor is the bit that's a different colour on the right hand end.
Here I've moved the decompressor from it's locating pin, it's a loose fit over the cam and this pin and it seems designed to rattle - I can't fathom how it wouldn't rattle!
I've ordered a new one anyway (they're only cheap) and at the same time I've ordered new camshaft bearings.
The one on the left is a standard part, but the right hand one is a Honda special (typical Honda).
There's a weeks wait for the parts and it'll go back together easy enough and if it wants to rattle then it'll have to just rattle.
You might be detecting a little "anti Honda bias" here and you'd be right - I really don't like Hondas, except for C90, CG125 and any single with the RFVC head, which started out with the excellent XBR500.
In the meantime the trusty GS750 has been pressed into service
I had another HT coil go last month, but it's back on form now. After 3 years of outfit riding I'm finally getting confident enough to really start enjoying the ride now, locking up wheels, lifting the chair, spinning the back tyre etc..
A bit of welding and grinding and I've produced this:
This is Bob's patent custom made SLR650 Rifle carrier, more on that later....