Search found 98 matches

by Looper
Tue May 06, 2014 8:17 pm
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

90 psi isn't too bad, and there clearly isn't a problem with the rings. Still think it would be worth testing the compression when it's hot and wont start. Should be higher but if not, it's possible either the valves or the head joint are opening up as they expand with the heat. If the compression h...
by Looper
Fri Apr 25, 2014 12:11 am
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

First thing is to lift the head and have a look, shouldn't be too hard on an old single. Any obvious scoring of the bore or rings, signs of a head gasket leak or badly seating valves can be seen once you open it up. There could well be one small thing causing a leak. A full topend rebuild is the wor...
by Looper
Thu Apr 24, 2014 9:12 pm
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

If as you said, the plug is a good colour and there's no problems while it's running the fuel supply must be ok (at least until you stop the engine that is). That's the bit that doesn't make sense to me, if it is a fuel issue I'd expect there to be problems while the engine is running as well. If yo...
by Looper
Mon Apr 21, 2014 8:38 pm
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

Might be letting myself in for a roasting here but as far as I know almost all petrol engines need at least 100psi to start reliably. Poor compression led me a merry dance in the past with a bike that was a poor starter, because I felt I had compression when I kicked the bike over. After doing every...
by Looper
Fri Apr 18, 2014 11:33 am
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

85 psi is low, I've always gone with 100 as really the minimum you want cold. If it's starting well from cold it might not be an issue, but worth looking at. Put a drop of oil in the cylinder and see if it increases, if it does it's rings, if not it could be the valves.
by Looper
Thu Apr 17, 2014 10:46 pm
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

I really would recommend testing the compression. If you've got spark, you've got fuel (while it's running at least), the third part of the holy trinity is compression. If an engine is hard to start but will run once started it's the first place to look. I don't know why you'd be loosing pressure wh...
by Looper
Fri Apr 11, 2014 2:09 am
Forum: Technical Advice
Topic: Hot Starting Problem Driving Me Nuts
Replies: 104
Views: 4832

Re: Hot Starting Problem Driving Me Nuts

Wish I hadn't looked at this post because after sitting here thinking for fifteen minutes it's still bugging me and I want to get to bed. If you've got spark when it's hot, and enough fuel's getting in to run when hot then surely it should start. I presume you've tried giving it choke. My triumph so...
by Looper
Fri Mar 14, 2014 10:25 am
Forum: Technical Advice
Topic: Making cables
Replies: 7
Views: 584

Re: Making cables

Thanks for the replies. I'll have a look on ebay for a kit and give it a go. I ordered cables for it a few weeks ago and two of the ones I got that were listed as being for my bike were wrong. As I have the old cables I can take the fittings and adjusters off and match up the lengths. It'll be a han...
by Looper
Sun Mar 09, 2014 3:16 pm
Forum: Technical Advice
Topic: Carb swap
Replies: 6
Views: 451

Re: Carb swap

Maybe it will fit so! I've a mate who's bike has a mark1, I'll take it while he's not looking and try it. Would be great if it does. That second photo.......I've seen a few B31 customs and they always seem to look worse that the original. Thanks.
by Looper
Sat Mar 08, 2014 6:32 pm
Forum: Technical Advice
Topic: Carb swap
Replies: 6
Views: 451

Re: Carb swap

A replacement 276 seems to cost about the same as it's name £276, I was thinking that at about £100 the mark1 would be be a lot cheaper but it looks to me that it would need some kind of extension to the inlet to get it to clear the dyno and oil tank which wouldn't be the easiest of things to make. ...