YL1.. Project thread

[m in sc]

and while the seat is being finished (he didnt like the ebay cover i gave him to use so is making one from scratch), i went ahead and fit the knockoff dyna-s onto the motor. since this thing lives at sky-high rpms, figured it was worth it.

I did NOT want to make it a non-reversible mod, so i had to get creative. modified the ignition trigger, bored it out a hair, milled the non magnet side flat (to accomodate a set screw), and hand cut a pickup plate.  I wanted to keep the elec starting as well.

modified magnet trigger:



mounted, then trued on the lathe since this was going to have the 'low' spot on the magnet side, i had to turn it a bit assembled.

I do know i could have used a sunken set screw to mount it, but wanted an externally accessible screw i used some case sealant in the gap as some 'insurance' it would stay put. I did not mod the points cam, so this can be taken off , wire wheeled and be used for points.



drawn template for pickup mount to bolt on. I have some being laser cut but i got impatient and made one by hand.



bare points plate:



mounted:



mounted with temp wiring:



running. advance unit is noisy w cover off.

[Kawtriplefreak]

Sounds great

[m in sc]

thank you. hopefully will be at gap in may to cause my own mini traffic jams. 

[m in sc]

nothing major, but got my laser cut versions of the ign plates (only needed one) and an nos oil pump cover.

[m in sc]

got my seat back for the little YL1E today, was hand made cover/foam and is absolutely accurate to original . Bill did a fantastic job as usual. used a correct reproduction cover , but with thin material, as a guide. the stenciling on th eback was sone with vinyl dye and a die cut template.

Dare is say its done for now. 







i made the pan repair so it didnt rest dead on the tank on purpose, but i am sure it will settle onto it a bit over time.

[Striker1423]

Dressed up looking spiffy!

[SoCal250]

Looking sharp!
You're making me want to install an electronic ignition in one of my RD125s. It would be a little easier as there's no governor to deal with. Hmm...

[m in sc]

would be easy. thats the advance unit for the starting feature, the regular YL1's dont have them, just the 'e' models. so, like 1 year production. thats why i had to mod it. 

[m in sc]

so, 4th was super tall on this, could actually hit a higher speed in 3rd than 4th. even though the gearing was stock, decided to go up 2t on the rear sprocket, was def worthwhile doing. can hit 55 or so in 4th now and actually maintain speed up a hill w out shifting to 3rd and screaming it.  small bike victories. saw 64 on a slight downhill  on the testride. also.. the sprocket carrier nut was chewed up pretty good. turns out a stock rd350 front sprocket nut is the same thread but larger hex... had to relieve the back side a bit to clear the chain adjuster but much better.   

[dgorms]

Saw 64 on a slight downhill! Holding on for dear life!

[m in sc]

so, rode it in yesterday, and its just not making the power up high i think it should... albeit it does run well.

i don't get it, everything is dialed in like it should, dead stock by the book except the dyna ignition.

Im going to throw in a new set of coils since i still have the originals in there, maybe they are just not up to the task at high rpm. Not missing, smooth as glass but? i checked the gps, it was a max of 52 mph and not that i need to go faster, but its supposed to go a bit faster. slightly frustrating. it has a fresh topend, cleaned pipes, baffles, stock filter and airbox, jetting, and the plugs look good. and im not -that- fat. lol. 

[1976RD400C]

Are you hearing a good popping sound from the exhaust, like it is nice and clear? Mine had a few bits of carbon break loose and plug those tiny little slit exit holes in the baffle.

[m in sc]

yes, they sound good. i cleaned the baffles a few mos ago, but do plan on looking at them again incase some shit boke loose.

[m in sc]

for those interested, update:

Thurs night i did swap the coils to new ones, got some emgo round bodies that people used to use on rds a lot, direct stock fit on this. that seemed to help the midrange a bit.
yesterday, i checked fuel flow, seemed ok but the tank vent seemed a bit.. lazy to breathe, so cleaned it, also looked at petcock, all seems to be ok. of course, i caused a leak so had to address that with a new wavy washer.

so pulled baffles today, there was 'some' shit that had broken loose, but not enough to clog them. i did open up the spark arrestor some, should allow any carbon to get thru now. vacuumed out the pipes with the shop vac, they are super clean inside now.

checked everything, went out and rode it, hit a gps 56 mph, speedo was reading 63 or so. lol. might have been some GPS lag but its running perfect, just slow, so i guess it is what it is. The up 2 teeth on the back sprocket didn't seem to hurt top speed at all, or help it, but it def helped midrange and 4th gear climbing whereas before 4th would just bog down.

I mean, its a 56 year old 100 cc twin... I'll live with it being a snail. but man its fun. 

[m in sc]

quick ride video.

camera is right over the left pipe mounted off the plate, so its a bit... loud. 

top indicated speed on this run was about 58-59.which means i hit 53-55 probably.