The Kick start Chestnut

Starting. The definitive answer!!!

So one year on, this is what Ive found out..

Yes...older bikes - technique is all important assuming the bikes set up right.

Now here's the thing...I couldnt be doing with all the hassle and to be honest it was putting me off riding a little - mainly because I was concerned if I dumped the bike off road I'd 1/2 die trying to start it.

What did I do....gave it to Taffy...(I hope he might add to this post to explain better but this is my take on what hed did).

Top end re-build - new rocker bearings - tensioner blade - valve seatings etc etc but the main things were:

1/ The Taffy crescent mod - see the doc - this makes the kickstart engage right from the top so you can get momentum for a full 180 degree of kick.

2/ New shape auto de comp lobe. I believe he had to mill down the cam shaft or something but I'm sure he'll explain.

3/ Other bits & bobs as it was there, but these were the main things.

THE RESULT IS......

Hot or cold it starts off the original re-starter system straight away. (I have the ys??/whatever battery everyone keeps going on about - this came with the bike & I keep it on trickle charge).

Hot or cold it starts of the kick start 1 - 3 kicks and no messing about trying to find TDC, just get on - choke on - one twist & release of throttle - 2 kicks & on the road (or track).

Went out the day it came back from Taffy and dropped it twice in some dirt tracks...stank of petrol - flooded...pressed the button..3 seconds and off I went again.

Dropped it again - flooded again - tried the kick twice & off I went again.

This morning..late for an appointment - car would get held up in traffic - jumped on the bike - and off I went - no hassle - what a joy.
Really what a joy - its fun to tinker with your own bike, but having it upgraded properly is something else.

I cant wait to fall off again...

Grinning ear to ear..

Thanks Taffy.

RE: Starting. The definitive answer!!!

thanks for that james

it was nice to have a top end job that was hassle free. i've got about 8 rebuilds in and they're all a nightmare....

what you said is essentially right. the battery you mention is the YTZ7S that is standard nowadays.

basically we got rid of the compression at cranking and then made sure that you had the right leccy bits and now the kickstart mod. so either way she's a goer!

can't understand why others aren't doing it too.

i have done a similar type of job for loonyberg (paul) but his is still harder to kick over than yours and the leccy boot also struggles. i have decomp issues with it as discussed in another thread this week.

his starter, like ned's just won't turn it over quick enough and yet he has the honda CBR600F4 starter on it. so next stop is the yamaha R6 starter.

i'm tempted to say that the honda starter isn't good enough. i wonder if ned would unequivocialy agree with that?

have you changed your kicking stance yet james?

regards

Taffy

RE: Starting. The definitive answer!!!

Yep, as you showed me, nuts right up on the fuel filler cap. Still some practice to get in but this stance is much easier. Also cause of the crescent mod you did, the kick has even resustance throughout, so sitting forward as above, once comitted to the kick, it is easy to follow through without the uneveness (lumpyness) of how it was before.

This evening at dinner, Sue asked me to pass the salt.....I got on my berg to do it. It's that easy to use now.

RE: Starting. The definitive answer!!!

Well my bike is completely different since Taffy had a go at it. At the moment it's more difficult to start from cold than before since the mods however I suppose the technique needs to change. I've also got a smaller choke jet to fit. I might also see if the R6 starter motor works as I'd rather have the button as a back up.

All in all Taffy once it's going it's like s**t off a shovel...v smooth but v quick!!!

RE: Starting. The definitive answer!!!

i need to have another look at that decomp paul. it's just not working right. i did one a month ago and the spring had jumped around the shaft and unleashed itself. the problem with the new deep groove is that to get the spring into it you have to open it up to get it there and unlike most springs, the inferior quality of these means that they make a new shape rather than return to the old one.

finding a cam one tooth out makes you feel good because you know the bike must run better. dead chuffed with the carburation change.


james
maybe some others will do it now. i did it three years ago and as i'm aware nobody else has tried it. i didn't renew your atomiser and needle but one day you can do this.

regards

Taffy

RE: Starting. The definitive answer!!!

i thought i'd jump in with some comments about my 650 project bike. after fitting the r6 starter and a new oldstyle decomp, all was well with the estart, but i am finding that the auto decomp is very erratic. i may be running ino the same issues with spring binding that taffy is seeing. it seems that at times, it acts like the decomp is stuck in the down position. i have run into this before, and thot maybe the spring had unwound, pulled the cover and couldn't find a problem. the decomp bob would rotate freely back and forth. after removing the selfdestructing counterbalancer last week, it is back to the point where it seems bound down. the kickstarter has a lot of resistance which is not there when you pull the bar lever leading me to think that the thing is not rotating back again. first thing i will do is see if the exhaust clearance is right even tho it was done with the engine on the bench and was right when it went back in the frame. although its very easy to start with the kicker, its THE PRINCIPLE OF THE THING.. :angry:

Re: RE: Starting. The definitive answer!!!

Taffy said:

his starter, like ned's just won't turn it over quick enough and yet he has the honda CBR600F4 starter on it. so next stop is the yamaha R6 starter.

i'm tempted to say that the honda starter isn't good enough. i wonder if ned would unequivocialy agree with that?

Taffy

Click to expand...

cheers ned

i will make this observation. the spring just doesn't feel like it is 'quality' - there is no ping, no pazazz to it. it coil binds, it's not strong enough anyway, it has to be bent tighter to fit because the 'D' at the cam end isn't tight enough. then you go and fit it and you have to get it over a little hump on the decomp. and this changes its phucking shape again!!!!!!

also ned, when it's sat with the decomp weight under the cam; the bloody spring hasn't even got the energy to lift the lobe back into the middle!

all in all - unimpressed. i've had three good springs and 2 poor recently and mine makes it 4 - 2.

maybe that little hump needs grinding off
a small .005" shim putting at the end of the shaft to keep the weight from thw cam shoulder
maybe the old spring

regards

Taffy

Just to add. Both my Bergs start first kick hot or cold, so it's definitely possible

mine starts first kick, too. its the estart/ auto decomp issue that's taxing my patience. :roll:
i can pull the choke cold, hit the magic button and if it doesn't fire right up. push the kicker thru with my hand and its like there's no auto decomp. i then start it using the kicker, ride it a 1/4 mile, shut it off, and it starts right up. go a mile and try it again. won't start. pretty much like a woman (if i remember correctly).
taffy, where would you put a .005 spacer? on the outside by the bob weight?

forgot ned but i tried it with loonyberg's bike and the shaft is right in the corner of the cam and there is no room for a shim at all. i even took one of the tiny, tiny 'O' rings that go on the head and there wasn't room for it so i stand to corect myself here. i'd forgotten i'd tried it.

the sprhg is weak and if you try and make it strong it jumps round the decomp. i think the answer is to get rid of the hump that acts as a side to the gulley that the 'D' part of the spring sits in. in the photo below its the shiny silver part above the spring:




that way the 'D' shape can be made real tight, the spring can be wound right up and because there is no shoulder it won't be coil bound. if it isn't forced hard against the cam's shoulder it will run free and it'll work!!!!!!!

could try leaving the smallest lip but nothing was stopping the old decomp from walking out the cam and it still didn't so........!

regards

Taffy

taffy, are you dealing with the oldstyle decomp or the dutch clog? my problem is with the old style. i've never had a problem with the dc type in my 04.

thats the thing ned. the dutch clog is what i've been on about and when you retro fit them they rub....

we'll get there!

regards

Taffy

i thot that looked like the newer style in yer photo. i think my new "oldstyle" bob stops wherever it feels like it. after i left the message this a.m., i went out and pushed the kicker thru with my hand and it stopped dead at tdc, so i pulled the bar decomp and kicked it thru a few times. after that, i could push it thru easy. then it kicked to life first kick and me in my sandals. while its running, i notice the weep hole dripping...jeesh. ya gotta love it. i need to get a new mechanic.
i guess i'll be experimenting with spring tension soon.

paul (loonyberg) came over today and the sole purpose was to grind the end of the slit trench away and leave it with a cross section shaped 'D' this will allow the spring to loosen it's shoulders a little. measured the spring as wound up a full 360d from 'natural' state.

in the few starts we had here the decomp was working more freely and although slow to kick through as ned says: it didn't have the bumps that the failing decomp had. it might have helped with an annoying little "ting-ting" type noise that we think was the decomp fluttering???

one thinmg it has occured to me that the 'boat' decomp has got that the later ones don't is a fine groove around the shaft right over at the other end of the springs seat. as the decomp comes through the cam there is a fine groove that the decomp spring drops into therefore stopping it from slipping out of the cam.

we're only talking about 1mm because the cam bearing acts as a buffer!

i will upload a photo to eric.

anyway, we'll see.....

regards

Taffy