Sipapu and OK on the flat, but way down on power on the hills

Readers may remember that a few months ago the 2014 plan was to push the No Excuse Cub through all the MWVTA ITSA events and see if all the frame and other mods had been successful.


Need to test all the mods for 2014

Rounds 1 & 2 didn’t get ridden as I was sidelined driving the school bus to Denver but we did get to ride at Sipapu NM where this current saga really begins. Sipapu is up there in altitude and it was also pretty warm and the faithful Del Orto didn’t enjoy either! The carb which was set up by Martyn Adams had performed flawlessly at all previous altitudes since fitting in 2007. It seemed perfectly happy from sea level up to 7000′ without any need for rejetting and only once felt down on power at Turkey Rock when the temp was in the 90’s …….. but all the other Cubs were having the same issues.

New jets were immediately ordered and fitted and then my Master Guru suggested I should consider upping the compression by changing over to a domed 9:1 Hepolite piston. Of course normal trials compression was always 7:1 but Ray said this was a noticeable increase in WOOF! He had some pistons and some spare barrels in his vast stock and would rebore one and send same. He also suggested I send my head over and he would vapor blast it on his new machine and maybe put some new valve springs in.



Off with its Head !

Head leaves, time goes by, and the problems start! Under normal circumstances this would have been back by the end of June in time to rebuild for Turkey Rock (mid July). At this stage the Safari is also causing mega grief with its generator. Finally the generator gets fixed but only on the day that we would be leaving for TR and with the Cub still not complete the whole mission gets the big CNX.

The planned piston fails inspection so another has to be sourced and the rebore now goes ahead. Meanwhile the head is stripped and goes through vapor blasting.

cub head 1

cub head 2

Through the blaster

Seems the valve guides are not good so the head gets a complete makeover and is now in intensive care.  NEW just about everything later its ready to leave and arrives in Dolores on Saturday last.


Head reworked and rebuilt


Piston and friends at the ready


ALL together and ready for homecoming

Despite my searches of the box the vital gaskets are not there and so the build is stalled once more!! They are now coming from both sides of the country in the hope that just maybe I can get her ready for the event.

Looking at “No Excuses” I see the tire has crept a little and on further inspection I also notice it  needs to be turned as the leading edge has gone. Might as well do the job properly.

First set of gaskets arrived yesterday but I was in the middle of other tasks so it joins the to do list. The lawn has now moved up the priority scale and is Thursday’s No1 and then the Cub leaps in at No 2  with Safari axle bolts at No 3 which are scheduled for 3 pm after which I can complete the fresh water tank cleaning that was started yesterday. Cloroxing 100 gals then draining and refilling once more, tedious task but has to be done.

Lawn gets done, back wheel out and tire off and the rim locks or security bolts have shed their rubbers ! Something else to do but this is trials so what did you expect?


New ones or repair these ?

Time for the bus barn and those grade 8 axle bolts via Jack my No1 mechanic. The road into town is being  repaved so try and set off nice and early but the bloody steps refuse to come up. At the Barn it seems the step motor is toast so we disconnect it and wire them up. The NEW bolts go in and I’m home again some time after 1730. A beer is required while security bolts are cleaned and re-glued.


New bolts fitted after the “steps” fiasco !



Glued ready for Friday fitting


Refitted after the turn


Man’s gotta have an edge!

A quick look at the new gaskets and I’m doing a double take!! the top push rod tube gasket has a cut in it !! how can this be? Is the World determined that I shall never ride this Cub again?


That green one looks an odd shape?


A great start!!

Friday morning and a call to the East Coast and they will send more but the show moves on and the tire is turned, back on, and pumped up.

Saturday and the CA gasket delivery finally arrives and having been sent EXPRESS Priority mail it takes 4 days instead of the 3 or even 2 for a letter! We can rebuild her, if I can find the time amid the last few days of getting this trial finished.


Priority EXPRESS, takes longer than a standard letter


I think I have enough NOW

The rebuild begins! The gaskets are rubberized and dried, the piston goes on and the circlips are fitted. So far so good, but first attempt to get the barrel on defies all logic. Dismal failure and with failing eyesight and no nails the project is abandoned for the day.


I give up! you win………

Will give this another mind bending go in the morning as it was exceedingly frustrating ….. you know what to do but just can’t make it happen…… a problem exacerbated by pudgy trials lumberjack fingers and NO nails! …… and old eyes to boot.

Had this been a Yam the whole job would have been 5 mins tops but, it isn’t, and now calls for some serious thinking. Because the barrel is a complete circle there is nowhere to squeeze the rings and trying to stabilize the piston as you lower the barrel down the 4 studs while trying the squeeze the rings is more than I can do……… thinks bubble? “where is the old barrel and piston?” Barrel located, upside down on the bench and after 5 mins the piston disappears like a rabbit down it’s hole. Now all that remains is to lower the pot/jug and piston down the studs and then slide the gudgeon pin in and fit the circlip.


Cat skinning begins! This should work, 1st test of the “old”

At least using this method I should be able to guarantee that the rings will have the desired 120 offset. More Guru tricks and know how as I’m told the rings are marked top on one side…… never knew that, and they are slightly tapered. Fit them upside down and it will smoke like a WWII destroyer on escort duties.

Wednesday morning, all’s quiet, time to sneak into the workshop and try the theory with the new one. Good theory! Barrel and piston now on with very little effort …… happy chappie!


All connected using “my” technique


I think I have run out of time (AGAIN) but it should be to done for Casper


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