[ryka]

Hi I am new here so be gentle ha ha
I recently bought an XRV750 RD07 1993 as a non runner.
I replaced the 30 amp fuse and voltage rec and bike was running pretty quickly.
the bike was surging and spluttering mid range and was hard to ride due to power was inconsistent.
so stripped carbs and done rebuild but the previous owner had put in the emulsion tubes with thread seal??? and the mixture screws were snapped off, so it was a mission to get rebuild done due to obsolete part.
replaced the following diaphragms, emulsion tubes and the usual rebuild kit on carb, spark plugs all replaced, clean fuel, fuel filter ,air filter and two coils to front cylinder because the leads were too short and new voltage rec unit and new battery.
bike won't start but mixture screw set to two and a half turns out as starting point. bike just back fires very loudly.

stripped carbs three times now and even put a different set on and same issue.

I was thinking that maybe fuel pump stuck on and over fuelling carbs but nothing coming out of overflow tubes.

looked at fuel pump and the wire snapped to the contact on removal and now can't get until shops open.

Anyone had similar issues???

also sorry to go on but I have 90psi on compression both cylinders just turning over on starter motor book say 150 to 200 at 4000rpm but can't run so can't check any further.

thanks for reading the long explanation

 

[Bardley]

Not necessarily a carb issue there..
Have you checked plug leads and timing? Are the leads def. On the right cylinders, and/or plugs.
A backfire after you've taken the trouble over the carbs tends to make me think electrics.

Sent from my SM-G955F using Tapatalk

 

[ryka]

Not necessarily a carb issue there..
Have you checked plug leads and timing? Are the leads def. On the right cylinders, and/or plugs.
A backfire after you've taken the trouble over the carbs tends to make me think electrics.

Sent from my SM-G955F using Tapatalk

thanks for replying yes leads are correct as it was running previously, timing is non adjustable but waiting form friend to come over with timing light to take a look. my next port of call is going to be timing and cdi unit I think. also one note to mention this bike has been VERY hard to try and get mixture anywhere near right before the carb was cleaned. I do have a stator plate that's new that's not been fitted yet but getting 14 volts from existing one when running.
not sure if the pickup for the coils is on his bike yet. been going down carb route too much so far. arghh
tanks again for replying anything helps with another opinion.

 

[een705]

More than likely its your cdi unit I have a working spare one where are you based

 

[ryka]

Hey that's cool but I am in Brighton but travel around south of England a lot.
I don't mind purchasing from you and resending back once tried, if it was the cdi unit I would probably purchase new one after.
I intend changing all the common issue items gradually just so I know bike should be reliable for next person if I ever sell it ha ha
I just don't want to put you out.
Let me know your thoughts about CDI unit as I said I dont mind buying off you if needed

 

[ryka]

Thanks to een705
For the icu unit
Replaced this and all ok
Lots of issues on the bike when I bought it but finally got it out on the road.
Still a a few niggles but will get there.

one thing I did notice was that when issues started the rev counter would fluctuate a lot up and down instantaneously even as the revs were going up.

maybe that’s a sign the icu is failing ??

 

[een705]

Glad you are all sorted now.