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It sure sounds like a timing problem.......either spark or valves. If the seller was honest and the engine was running then the valve timing should be good, so spark is the possibility. Try swapping the stick coils on the plugs as a quick fix, or at least to see if it makes any difference.
 

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Discussion Starter #22
Had the carb off and doesn't look like the there is a gap in the inlet manifold. It does look a little dirty on the other side of the inlet though (see picture).

I also tried holding the carb near the inlet plugging everything in and turned it over and didn't see any fuel being put in from the injectors. Then tried spraying directly in without the carb attached and did see the spark ignite inside the engine but nothing afterwards.

Will try the compression tester when it arrives.
 

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Looking over recent posts it sounds like there might be a problem with both the spark and the fuel.

double-check spark again
if either the plug wires are reversed on the plugs or the harness wiring to coil connections are reversed, the timing will be off by a huge amount.
spark but no bang.

fuel - are you using the stock fuel pump?
if using a fuel pump from an engine with carburetors, the fuel pressure will be too low for a fuel injected engine.
also fuel pressure may vary among different fuel injected engines?
 

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The two screws at the bottom are for bakancing the throttle body for idle. Don't touch them if you have no balance tester.
Btw you comfused me a bit, in previous posts yoi said many times that you're running carbs, but this is the oem throtrle body and injectors.
You shoukd definitely have petrol in the cylinder, on thevplugs and in case the engine is not firing in the exhaust.
Imho if you don't feel fresh unburnt fuel, you have to look aeound rhe fuel system first.
 

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There also seems to be a lot of crud and grit in the throttle bodies. What do the intake ports in the head look like? If they're gritty too a compression and leakdown test are vital. If the engine had ingested a bunch of dust and grit for some reason there may be cylinder wall damage that could cause low compression which might then lead to hard-starting.
 

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My guess is you have a valve not seating after seeing all the debris on the butterflies, compression test will confirm that.
 

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Try it with the side stand up, mine sounded the same a few weeks back and the neutral switch was worn so on turnover the switch was vibrating meaning the ECU was thinking it was in gear and not starting on the side stand.
 
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