Honda ST70 Engine Start Up Tip?

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willmc
Posts: 10
Joined: Mon Sep 14, 2020 5:00 pm
Rides:: Honda ST70

Honda ST70 Engine Start Up Tip?

Post by willmc » Mon Sep 14, 2020 5:12 pm

Hello All,

I have a very good condition Honda ST70 which runs well and has been well maintained. However it often goes without running for 6 months or so at a time and when we go to start it it takes a bit of fiddling to get it up and running.

Can anyone recommend tips on go to areas on the bike to maybe check/clean/inspect prior to start on cold engine/not started for 6 months or more? Any parts of the engine or electrics that are known areas to make it difficult to start?

Let me know your thoughts, thanks all.

Will

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Alan CF
Posts: 6750
Joined: Mon May 09, 2011 6:10 pm
Rides:: CUB RACING small cc engine rebuilds crank repairs
Location: CHESTERFIELD

Re: Honda ST70 Engine Start Up Tip?

Post by Alan CF » Mon Sep 14, 2020 6:52 pm

First thing would be to replace the fuel.

JOHNBOY
Posts: 1705
Joined: Sat Apr 13, 2013 2:03 pm
Rides:: HONDA SUZUKI

Re: Honda ST70 Engine Start Up Tip?

Post by JOHNBOY » Mon Sep 14, 2020 9:06 pm

your problem is fuel these days contain ethanol which draws vapour rust in tank doesent last long the days are gone when you could leave petrol in tank for long periods

Dave48
Posts: 62
Joined: Sat Jan 28, 2017 11:16 am
Rides:: HondaC90-G(1992) Cub,Yamaha Tracer700(2016)
Location: Birmingham West Mids

Re: Honda ST70 Engine Start Up Tip?

Post by Dave48 » Tue Sep 15, 2020 6:10 pm

Yes modern unleaded fuel goes "off" pretty quickly. Some including myself have tried adding proprietary fuel stabiliser-one that comes to mind is Forte petrol treatment. It's worth a try if like me you have to leave bikes in cold damp environment over winter and a full tank helps reduce internal rust but the ethanol in fuel attracts moisture from the atmosphere. Untreated tanks can develop fine rust particles that play havoc with small jets if they get past the filter.

willmc
Posts: 10
Joined: Mon Sep 14, 2020 5:00 pm
Rides:: Honda ST70

Re: Honda ST70 Engine Start Up Tip?

Post by willmc » Tue Sep 15, 2020 10:36 pm

Thanks for the reply all, thanks for that info also Dave48.

So if I use the Forte treatment you think this could help me get the ST70 going and then also help maintain when not being used for some time?

If there are any other recommendations to get the ST70 going over some time of non use let me know.

Thanks all.

willmc
Posts: 10
Joined: Mon Sep 14, 2020 5:00 pm
Rides:: Honda ST70

Re: Honda ST70 Engine Start Up Tip?

Post by willmc » Wed Sep 16, 2020 12:11 pm

Also one more question - does a Haynes manual or equivalent exist for the ST70? If so can anyone recommend?

Thank you

Dave48
Posts: 62
Joined: Sat Jan 28, 2017 11:16 am
Rides:: HondaC90-G(1992) Cub,Yamaha Tracer700(2016)
Location: Birmingham West Mids

Re: Honda ST70 Engine Start Up Tip?

Post by Dave48 » Sat Sep 19, 2020 6:55 am

Hi willmc,
I received your pm yesterday when I logged onto forum. I replied via pm but message doesn't show as sent. I am not the most up to date with new tech but if you wish me to answer your query send me an email velocidave at hotmail dot com & I will answer asap.
Dave48

edited to hide email from bots wightegi

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