G
Grant
Guest
Maybe the UK market was different.
My info came from the UK importer direct.
My info came from the UK importer direct.
Pulling apart the faux Montjuic
- Thread starter AndyB_11
- Start date
A few minutes with my favourite search engine reveals nothing about S2 cams so I've not got a clue where that came from. It may be that I misheard (or remembered) what I was told but that's not a big deal. The actual stamping on my cams is 1S rather than S1 but that's probably how they're all stamped and just another reason why I thought I'd got 'standard' cams.
My understanding is/was that the Alpino S had different cams and pistons to the Montjuic but my bike having originally been an Alpino S suggests that either someone threw money at it or they did indeed share the cams.
My understanding is/was that the Alpino S had different cams and pistons to the Montjuic but my bike having originally been an Alpino S suggests that either someone threw money at it or they did indeed share the cams.
phil37
Hero member
- Location
- Lincolnshire
In the Uk the std cams for the Alpinos were marked "14" - the early models didn't have the higher comp pistons like the Montys but later models did. The "S1" cams need the head relieved at the top of cam bucket bore to avoid oiling problems. - regards - phil
sonicboom500
Hero member
The cams in my Monty would struggle to rotate without the relief slots in the cambox floor.
One of them had a bit of a shine on one side so I widened it slightly.
May have always been like that or might have been from an earlier drama.
Careful when you stick the cambox gasket down as their is not much clearance on the lobes when flat.
One of them had a bit of a shine on one side so I widened it slightly.
May have always been like that or might have been from an earlier drama.
Careful when you stick the cambox gasket down as their is not much clearance on the lobes when flat.
Ok, I'll use feelers to check the clearance next weekend even though the lobes don't look as if they've been rubbing on the head but is there a minimum clearance?
Todays good news is that a genuine petrol tank arrived at home (after I'd left for work) so I'll have a look at that on Friday and see about getting it sprayed along with the seat and fairing. I've not seen the tank but I'm assured it's in fairly good condition, no rust and only one or two minor dings and scratches to sort out so I'm more than happy with that because the bike previously had a badly sprayed Alpino tank on it and it looked crap.
This had better be worth the effort!
Todays good news is that a genuine petrol tank arrived at home (after I'd left for work) so I'll have a look at that on Friday and see about getting it sprayed along with the seat and fairing. I've not seen the tank but I'm assured it's in fairly good condition, no rust and only one or two minor dings and scratches to sort out so I'm more than happy with that because the bike previously had a badly sprayed Alpino tank on it and it looked crap.
This had better be worth the effort!
sonicboom500
Hero member
Oh yes.
They sort of disappear when they are all working properly.
Just get used to riding at the back of any group and carrying spare earplugs for your ex friends.
The relief slot on mine is pretty obvious, like someone took a grinding wheel to the top of the cam bucket guide
They sort of disappear when they are all working properly.
Just get used to riding at the back of any group and carrying spare earplugs for your ex friends.
The relief slot on mine is pretty obvious, like someone took a grinding wheel to the top of the cam bucket guide
Next stupid question....
I've checked the compression with a calibrated gauge and it's showing 110psi on both cylinders but I haven't done the next stage of pouring a small amount of oil in the cylinders to see if that changes the readings. It's bloody freezing in my workshop and I can't be bothered heating it up just for 15 minutes of work this evening so it can wait until tomorrow.
Does this sound reasonable?
I've checked the compression with a calibrated gauge and it's showing 110psi on both cylinders but I haven't done the next stage of pouring a small amount of oil in the cylinders to see if that changes the readings. It's bloody freezing in my workshop and I can't be bothered heating it up just for 15 minutes of work this evening so it can wait until tomorrow.
Does this sound reasonable?
phil37
Hero member
- Location
- Lincolnshire
Hi Andy - With the large overlap on the S1 cams - the readings are lower than normal unless you could spin it up a lot faster! - Regards - Phil
Laverdaton
Hero member
Can someone post photo of the relief slots........
The "S1" cams need the head relieved at the top of cam bucket bore to avoid oiling problems. - regards - phil
Thanks,
Andy
The "S1" cams need the head relieved at the top of cam bucket bore to avoid oiling problems. - regards - phil
Thanks,
Andy
Thanks Phil.
I've only been cranking it over on the starter motor and even though the readings initially seem low I'm grabbing some compensation from the fact that both readings were identical.
I'll warm the shed up tomorrow morning and have another check with no added oil then drop a bit down the bores and see what happens to the readings. Even though the guy I borrowed the tester from says it's calibrated I can't be 100% sure but another way to check is to take a reading off a different bike and see if that one appears low. It's a push fit tester rather than a screw in one but the fact that both cylinders read the same makes me think I've got it seated ok.
I've only been cranking it over on the starter motor and even though the readings initially seem low I'm grabbing some compensation from the fact that both readings were identical.
I'll warm the shed up tomorrow morning and have another check with no added oil then drop a bit down the bores and see what happens to the readings. Even though the guy I borrowed the tester from says it's calibrated I can't be 100% sure but another way to check is to take a reading off a different bike and see if that one appears low. It's a push fit tester rather than a screw in one but the fact that both cylinders read the same makes me think I've got it seated ok.
It suddenly dawned on me this morning that testing the compression with the throttle WFO would make a difference so after an hour of pre-warming the shed I took myself off with a cup of tea and a Marlboro Red and had another go.
Result! 154/156 dry then I gave more cylinders a quick squirt of WD40, left it to seal the rings a bit and checked again and it was reading 156/158 so decent enough readings to start and only a minimal increase after the WD40 was added.
Given that the valve clearances were bang on, the cam is in good condition and it wasn't smoking last time it ran I reckon I'll be leaving the engine as it is for a while.
Result! 154/156 dry then I gave more cylinders a quick squirt of WD40, left it to seal the rings a bit and checked again and it was reading 156/158 so decent enough readings to start and only a minimal increase after the WD40 was added.
Given that the valve clearances were bang on, the cam is in good condition and it wasn't smoking last time it ran I reckon I'll be leaving the engine as it is for a while.