Honda-SOHC

Update:  I ended up going back to the USA before continuing with this "project."  While there I came across a complete points plate/advance unit in a garage sale for 10 USD!  I checked the condensers  with a real capacitor tester (not a multimeter) and they show good as far as capacitance and voltage.  Points are original ND and look essentially unused.

Now I'm back in the UK eyeing these parts wondering whether I REALLY want to install the OEM system or just leave the perfectly functioning DSS EI in place.  Logic/common sense would dictate leaving the EI; but I have this NON-common sense urge to have the points in there...

I haven't awakened the 400 yet from it's winter slumber - been too cold/wet for me but hope to do that sometime this week.  It's probably not often that someone has a perfectly running machine and intentionally changes something that may make it less so and I can't think of any operational advantage that the points would provide!   Yes, they will provide a spark with less voltage than EI but I haven't seen any case with my 400 where low voltage is an issue.     So more thinking...

Is it possible that the pipe thread on the "modern" sender you purchased and the pipe thread on the moto do not match?  There are three or four different specs for "pipe threads."  I have no idea what Honda used in the '70's vs what they may be using now.  But if they don't match that could be a reason for the seep.

I'm very new in the "vintage" Honda world.  Last year was my first experience buying parts for one (OTOH, I have LOTS of experience doing this with a Norton Commando over the last 18 years)!  FWIW, I bought my CB400 parts from three different suppliers in the UK.  DSS parts fit perfectly in all cases; the other two had around a 50% success rate "out of the box."  I realize I don't have the knowledge of the various suppliers that many folks here have but I was very pleased with DSS and the speed of delivery.  So, at the moment they are my "go to"!  I probably won't be buying a lot of parts in the future since my 400 is now pretty much "set" for (hopefully) years to come!

Oh, BTW, I was also EXTREMELY pleased with Nurse Julie's parts/immediate delivery! 

I have no personal experience but I have read and talked to folks that rather than buying new OEM-type/size condensers (now called capacitors), they have purchased known good quality capacitors from the various electronic suppliers.    They are reported to work well/have a long life.  As far as the spec, I seem to recall reading or hearing something like .22uF/1000V AND due to size/fitment that they had to be mounted externally, NOT on the points plate but I wouldn't trust my memory re any of that! 

I apologize if you are well aware of this but offer it hoping it might help...

Exhaust systems often do not align properly unless the various components are all installed but with all the fittings left loose.  Then, gradually tightening and, at the same time  some slight adjusting during the tightening process will ultimately achieve proper alignment.  Sometimes the alignment/tightening process will have to be "out of order" from the manual and/or logic!

My 400 has the DSS exhaust.  It was installed by a shop for the previous owner. Since I didn't install it I can't say anything about how difficult it may have been to install but it appears perfectly aligned.  Of course, one issue that can arise nowadays is that DSS (or anyone else) is selling exhausts made by whoever they can get them from.  Suppliers and their "accuracy" can change, affecting the ease of fitting though I would EXPECT (hope?) that any supplier's exhaust system would be able to be adjusted to fit the target moto properly during install. 

In any case, good luck with a quick and easy resolution!

I removed all the aftermarket hex head fittings that were on my 400 when I bought it and replaced them with the OEM JIS screws.  I much prefer the original look now though I admit that back in the day with my various UJM motorcycles I removed all the OEM JIS screws and replaced them with hex/Allens.  Go figure...

My wife and I are thinking of joining some friends who are doing a two-week tour of France/Italy in May on motorcycles.  They will be hiring motos in Italy.  We would be riding ours from the UK.

My wife would be on her Honda NC750 and though I have a current litre-bike available, I am thinking of riding the 400.   It is now my favorite motorbike to ride for the type of riding we enjoy...day rides on twisty back roads.  But that's quite different  from touring with the necessary "luggage" for several weeks of riding.  I'm also wondering if the hi-revving little four would lose some of its appeal in such use, becoming "buzzy" and annoying rather than fun.  Anybody done this sort of thing on the 400? 

Back in the day I rode my Honda CL350 across most of the USA but I was in my early 20s then and luggage/comfort were of minimal concern! But I don't even know who that guy was!