Classic MX des Nations bike prep

With two weeks cycling in France before heading across to the Classic MX des Nations in Northern Ireland, it was time for some final bike prep. Unfortunately this was more major than anticipated as the bolt up wasnt running well at Hanbury. Luckily Paul was around to lend a hand. 

I decided not to ride after my poor showing at Teifiside and that Andrew Owen was available again to make the trip. However was going to be a reserve rider so the 1970 Hallman needed sorting. Also the Bolt Up was going to be needed by one of the 70+ team so plenty to do with 1.5 days of intermittent shed time. 

First up a look at the 1970 bike which had gotten a second consectutive puntuce. Got the wheel and tyre off on Sunday night after Hanbury before even washing the bike (which Ive worked out a system for after plenty of recent practice).  Checking the spokes at the track indicated only one loose one, but with the complete tyre off quite a few of the nipples were loose. The wheel is a relatively new build carried out by Jan before he sold the bike so made tightening and adjustment relatively easy. In with a new heavy tube and sorted. 

Some other tweaking with the bike on Monday but attention moved to the Bolt Up. Changed the RH crankseal and checked the carb manifold gasket as well as cleaning the carb. However getting ready for a test and there was no spark. The ignition timing on the Bolt Up has been a regular challenge later on in the season. Testing the stator and coil resistance as well as the continuity between and all seemed okay. Some debate between Paul and I on the spark plugs but nothing. Adjourning for dinner and to think I went back out later and tried a Bosch rather than an NGK plug and a spark was there.  

Still not starting so squirted in some EasyStart into the carb mouth. Fired up though again the engine running too quickly. End on Monday and only a few hours on Tuesday to fix as I also needed to work. Some thinking and decided that to put the older Bolt Up engine from the ‘more original’ bike into the frame. 

Good plan which though easy in principle than practice as it seems no two 4-speed engines are the same (though they might initially look this way). Some have an extra bead for strength which means they do not fit some engine mounts. 

So plan C was revert to the ‘original’  bike with small hubs, side float Bing carb and very wide (but period) handlebars. Should be good for Brian Walker’s nostalgia. 
The lack of a front brake on the bike was due to ingress of mud and water forming a vicose paste across shoes and liner, which through some workshop chemical engineering Paul managed to resolve. The engine was placed back in to the frame and the carb cleaned. These fail in two ways whilst racing when the bottom bolt comes loose or if the float chamber gets grit into it stopping the float from dropping and allowing fuel in. 

Quick test up the lane and all good with only a slight rattle from the engine. Ready to a practice session up at the farm. 

And then news from ECMO that due to the low number of entries for the 30+ in Northern Ireland they were allowing second teams from England, Scotland and Wales. So I will be riding after all. 

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