Standalone tachometer

[PrinceRupert]

My 205 doesn't have a tachometer, so i need a standalone one for tuning carb etc.

Would a cheap contactless one do the job or do i need something more sophisticated?

[GreenV8S]

If you have access to the LT side of a coil the ideal would be an electrical one. Or you can put a dab of paint on the front pulley and use an optical one. Or use one with an inductive on an HT lead if you have those - although my experience with those hasn't been great.

[xstian]

You don't really need a tacho. I assume you want it to set the idle? This can be done by ear to be honest, its basically the slowest speed you can get the engine to run, without stalling or spluttering, probably somewhere around 900-1000rpm. Its not that critical and you will be able to tell the difference between 900 and 1400rpm quite easily. The idle might not need any adjustment anyway and if it does it should only be a tweak.

From reading your other thread, I assume you're planning to clean the carb? It's not particularly difficult, but you might want to do a little reading first. It's very easy to rip it all apart and then realize afterwards it would have been a good idea to check where the idle and air mixture screws are set at. Also some parts are screwed in and some parts are pressed in and are not designed to be removed for cleaning and are easily damaged with a poor fitting screwdriver or over tightening. You don't necessarily want to strip the carb of every component to clean it, so worth finding out the important parts to clean and identify them first.

Have a look for an exploded diagram of the carb and do a little research on cleaning carbs. Do you know what make and model the the carb is?

[PrinceRupert]

xstian said:

You don't really need a tacho. I assume you want it to set the idle? This can be done by ear to be honest, its basically the slowest speed you can get the engine to run, without stalling or spluttering, probably somewhere around 900-1000rpm. Its not that critical and you will be able to tell the difference between 900 and 1400rpm quite easily. The idle might not need any adjustment anyway and if it does it should only be a tweak.

From reading your other thread, I assume you're planning to clean the carb? It's not particularly difficult, but you might want to do a little reading first. It's very easy to rip it all apart and then realize afterwards it would have been a good idea to check where the idle and air mixture screws are set at. Also some parts are screwed in and some parts are pressed in and are not designed to be removed for cleaning and are easily damaged with a poor fitting screwdriver or over tightening. You don't necessarily want to strip the carb of every component to clean it, so worth finding out the important parts to clean and identify them first.

Have a look for an exploded diagram of the carb and do a little research on cleaning carbs. Do you know what make and model the the carb is?

Thanks, all well noted. Can I just take the top off and spray some carb cleaner around rather than dismantling it fully and then struggling to get it back together...?

[xstian]

Can you get a photo of the carb up, so I can see what type it is. Maybe take the plastic inlet off the top.

[PrinceRupert]

[xstian]

From doing a bit of googling looks like a Solex PBISA.

Have you got a workshop manual?

http://pdfstream.manualsonline.com/7/7f118b27-a3f1...

There is also an exploded diagram here, but it's not labeled

https://www.carburettorshop.com/drawings/solex_pbi...

You might find you won't have to strip the whole carb just clean out a couple of the jets and maybe the float bowl.