Honda-SOHC

SEP sounds like a good recommendation? I've no knowledge of them but it seems from what they have done for you that they can do the work to a level you need.

My reasons for being careful about skimming barrels is that they are hard to do correctly without some experienced engineering behind them, I've seen a few that have not been successful so If you can get this level of service it makes it much more of an option.

The cam chain comment I made is I believe relevant as if you consider when you adjust the drive chain you only make a small move in length but the slack changes out of all proportion to how far you've just moved the spindle. I'm not clever enough to do the calculation but it must have something to do with sprocket diameter, I don't think it's a straight no ratio effect though.

Hi

The brass tube will normally be above the fuel level with a correctly set float and valve and so have nil affect on any carburation.

BUT........... if the bowl continues to fill the fuel now has (outlet blocked) no route out other than through the carb and depending on arrangement, angle, etc could fill the cylinder!! IF this happens the cylinder will not pass compression when cranked over and will most likely bend the con-rod. I think the tube is important so would install replacement.

Even if it kept getting a small amount of fuel into the motor it is still ultimately drastic if left unchecked, bore wear, oil dilution, leading to bearing / cam failure.

Not trying to scare you, as if all is well then nothing, but it is an important contingency.

Hope this helps.

Sounds good, any pics for us to have a look at it?

They are a bit different to modern stuff, much longer and harder to change direction. They need some persuasive pressure that would have a newer race-rep straight upside down if used. It's much more like a big bore moto-crosser in that it's a lot of footpeg weighting and big pull of counter-steer to deviate it from straight ahead at speed, respectably quick though.

We had a small guy owned one early 80's and with ad-hoc drag racing (ahem, not on the public highway officer!!) that F2 would beat most things in it's era till CB900 Suzuki GSX etc came around.

Hope you enjoy it.

Here's a slightly different angle on it which may explain some of the experience old-v-new gaskets etc.

This era or production has covered the removal of asbestos from head gaskets so any original specs that used it would have to have been re-formulated. Commonly they went from asbestos to graphite and one of the characteristics that changed was it was more common for liquids to creep through the new ones, making it common practice to have a sealant where none was needed prior to this.

Graphite type gaskets also need retorqueing on some arrangements also and this is never part of the plan for SOHC 750 motors due to the need to remove from frame to work on. I'm guessing this but it may be why they are more succesful with sealant with the types available now both Honda and pattern.

There is a piece written in current "Classice Bike" along these lines, not specfically dealing with this application but if you overlay the info contained with our experience and the timeline involved I think you can form a more thorough resoning as to the use of sealant or not.

I guess this impacts many of the bikes on here.

Thanks for the effort of posting all that, really good. Seems that you had a good weekend out.

I guess I should say Cheers!

Hope you've got it with that, it's nice when they run well and you know you can get a reliable run out on it.

Didn't put enough detail in last post but the question about how big a skim has an impact on cam chain tensioner also as the total shift is doubled (2 runs of chain, up and down) so the tensioner will reach max tolerance earlier in the chain wear cycle.

Be interesting to see how you get on as I've never worked on one with a skim to my knowledge.