MRB 190 running issues

[the-brickie]

Right, built it and its double hard to start and will not run..

Exhaust 170
Trans 135
Inlet 165

Height over ports

Exhaust 35mm
Trans 45mm
Inlet 71

Reamed 26mm jetex and reverse cone VW clubby that I had working very well on a Stg 4 200 indian top end, stripped it all down and everything looks fine, gasket faces etc, piston in the right way ignition set at 21 BGM and indian standand flywheel. I had hoped it would just fire up and run sweet as a nut but no such luck I noticed that on Marks site they mention about the inlet being a bit dodgy

Any ideas as to why it will not run?

[RICSPEED]

can you tell us more about the inlet issue or link to it?

[soosh]

Does it actually start rev when you get it started?

[the-brickie]

This is the quote from the site,
'The differences show up when doing an old style Suzuki 190 tune. 5mm has to be taken from the base of the cylinder, the piston needs shortening to clear the casing at bottom dead centre. Then when setting up the tune and checking the port timings you find that inlet ports are abnormally small or too large and transfer timings can be spot on or far to big making the barrel slower than standard! For this reason I stay clear of this set up tune!'
But I may have been reading it in the wrong context. Think this refers to a TV barrel but then wasnt the Alloy barrels based on the TV port design?

Revs fine but no idle when I actually got it started which was hard and very frustrating.

Looking at the Webster book the timings arnt that far off these so I'm sratching my head as to why it will not run.

No air leaks, everything was tight and well sealed. Had to use 3 base gaskets to set it up to within 1mm from the top gasket face and will order a packer for when I next have a go.

The piston crown is not level with the bottom of the exhaust at BDTC, approx 5mm but as I've said was more interested in the piston crown to top gasket face, transfers ok.

[wack 63]

Sounds to me the carb / ignition is playing up.Does the choke work ok? and is the idle circuit clear.The port timings are ok although at 135 the transfers are way too large,the inlet is really designed to run a larger carb and will spit back a fair amount at low revs. Not quite sure about the 3 gaskets are you sure it isn't tuned for the TV or Yam rod? The cylinder base will be machined for a 58 stroke 107 rod set up.Personally I would set the timing 18 -19 degrees nowadays to be safe

[the-brickie]

Carb and Ignition was fine on my 200, in fact they were brilliant, just put the whole ignition on my TS1 now and its great, tried advancing the timing to 17ish (even retarded it to 24 for better starting) on the 190 still no joy, tried with choke on, choke off, choke on and it started (but I was knackered kicking the thing over so much) ran ok-ish but would not idle. Cleared all jets, cleared all passages the no change.

Barrel machined for a 107 standard rod, hence most of the timings being ok, but it has been thru a few hands and some of them hands really didnt know what they were doing.... dont think any of the ports have been messed with, just the choice of tools to 'hammer' the barrel into the casing! and then trying to get the barrel off using a crow bar by the looks of it! Without 3 gaskets the piston crown was past the gasket face, the piston would then also be above the bottom level of the transfers, so would it be better to pack the base or the head to improve timings?

[soullad]

I would have suspected the carb / ignition too tbh. Worth double checking these, esp jetting.
If you still have problems you might need to start again and go back to basics........

The standard sr alloy 190 barrel / kit was designed to be run with a 58 x 107 crank, with a standard lammy compression height piston. (39mm I think?). Ok the piston suffered from poor tolerance maching and the ports are abit rough and ready but cleaned up, its nice cheap top end.

What crank and piston you using?
Can you measure the total overall length of the barrel, from gasket to gasket face to make sure it hasn't been machined for a typical old school conversion? (107mm rod x suzi crown height piston.. 30mm)
Worn rings can give poor starting / idling - worth checking?

Just some initial thoughts..

[wack 63]

I had a Webster 190 done in the 80's with the base machined for the 107 rod and had to slightly modify the lug on the inlet(next to the long stud) because it touched the casing .The piston was level with the bottom of the exhaust port at BDC but was lower than the transfers.If your barrel is tight to fit to the casing I would suggest it is damaged and possibly trapping the piston at BDC? Really needs checking to be sure it is not warped.By the way is it one of those shonky Ebay ali barrels ?

[jonny snatchsniffer]

if using a suzuki piston wont it be 5mm off the bottom and 2mm of the top of the barrel for a 58/107 ? ive done a couple of these and some pistons ie the later type ts/pe185 have a narrower skirt which depending on how wide yr inlet is (cos the increased bore moves the inlet over) wont seal properly as there is a slght gap on the right of the inlet, is there a reason for you wanting a negative deck height of 1mm

[the-brickie]

Its a TS185 piston conversion, No. 1414, done by Mark, done to run standard rod crank, its a sil crank, I would have thought it an old SR barrel, no reason for the deck height other than a starting point (which hasnt worked..!) and I like to run with no head gasket, I've stripped it and am now building a work bench in the garage to re do it... the varitronics not selling so I'll try it with that.