a new member and new builder plus progress so far

Hello Derek , if you click the bike it'll play a video, then you can see the side view

Well done Dan
Next step lydden watch out for those motorhomes

yes yes done that already, you just need to make it easier for none tecko like me by saying that but Ihad already figure it out,

how do you load such a thing,

but I can not see the barrel, is it a 125 / 175 - is it iron or cast alloy, not one of brians, and if Imay say what a great job you have done,

it certainly looks the dogs tagems,

I love its historic look too I am very loud against modern fairings, think they just dont do our class justice or the riders/ tuners who put so much effort into making them Fly as many of them do now days,

I feel with the lower half its will look even more like a original racing fomula bantam, of the ciorrect erra, sounds gerat too,
what a great job.

lydden is where it will be chrisend, sadly its the start of my holidays as too Darley is at the end,

so Im not contemplating the cost of trying to fit in all three, if I dont make it be sure to get some more pictures signed up and make sure you put them on your own page, post see you been posting I feel this is will be really helpful to many others looking in, to see what can be done over a period,

while you certainly have some nice gear to do this, its nothing that is not available to others, from small eng companies, or within our liitle group of builders/tuners and racers.

regards Derek

Hi Dan I did the parades at Snetterton as do not have race licence sorted yet. They were great value; I got seven laps four times for £100 and had a lot of fun. If you get someone to take so times it will also give you an idea of how you might do in the racing when you get to that stage. I should be wobbling round at Lydden so it would be good to see you.
Smiffy

i've been having trouble with the pr6 download from the bhr web site, seems to be the wrong/same form as the pr5 ,i've tried calling the numbers to speak to someone but get no answers, have emailed and waiting to here , any one know how many sessions are planned for lydden?



just been called back , gerry will post the entry to me , ted , you may need to call him yourself to get the correct entry for the pr6 ,

could anyone tell me at what revs the noise test is taken for 175 bike , thanks

HI Dan
6700 rpm for a 175

out of interest i took the head off to have a look to see how its was doing, it all looks okay to my untrained eye, a little oily this wipes off with a finger tip , so far its not really been pushed rev wise, i have been able to do a dozen or so starts from a stand still but get to what i think is half rev's in second gear before i run out of room, what do more experienced eyes think?

Hi Dan

At the top of the picture of the head it looks ragged and burned as if you have had some detonation.

Detonation can be caused by a number of things - running weak, too high a compression ratio or too much ignition advance for the octane rating of your fuel.

Does the squish band spigot into the barrel ? If so the sharp edge may get hot enough to cause pre-ignition which has the same effect as too much advance.

Mick

hello mick ,

all the ragged bit you mention wipes off , its a run/film of oil , the squish doesn't spigot into the barrel its flat.

i wiped the head with a rag and took a few more pictures, to me it seem like it did when i put it together , and i would guess running rich , but thats only a guess as its so oily and wet, would you say its looks safe to rev it hard for a few laps? ,

i have run the engine a fair bit to date and has used almost 4 lts of fuel , i've stripped it down over the last month or two 6 or 7 times and stoned the piston removing any spots that looked like it was picking up and a light hone in the barrel. and today its got no more highs to rub , here a picture after i wiped it clean , not very good pictures as there were taken with a mobile.

Hi I think Mick is not refering to the head, deposits at all, this in my opinion can tell you nothing inportant,
Mick I feel is refering to the piston crown "" much more important in the mixture stakes, I have to say I agree with his prognoses, although I would ad you can see the meassls in the carbon on the piston crown too,

I would further add this engine will self distruct underload, if all you have been doing is running it up the road, thats if its left as it is, the only thing that is puzelling me me is the colour of the crown, I think it looks a tad on the rich side, and appears to be good colour, which would for me point to other things affecting this.

regards Derek,

Quote :

At the top of the picture of the head it looks ragged and burned

Quote :

all the ragged bit you mention wipes off , its a run/film of oil

Ahh - in that case I would say its a bit oily

I must say Dan its all looking very neat and well made. Well done and hope to see you out on it soon.

Mick

So would it be wise to set the ignition a little closer to tdc ?

Hi Dan I'm confused about the way your carb is mounted. It appears to have a bracket above the bell mouth fixing it to the frame. This would defeat the purpose of rubber mounting it from the manifold, please explain.
Agree with Mick, it looks the muts nuts.

Hello Ned , its a temp idea as the silicone hose I used to mount the carb is too flexy for its
Own good , I' ll be making the manifold again with a lip to help trap the hose on.

Hi Dan

I just looked back at your earlier posts where you said your ignition timing is 1.85mm btdc which is ok - personally I would start a little lower say 1.6 but there's bound to be some variation in advice here as a lot of things affect combustion - compression ratio, squish clearance, head design, fuel, how well the motor breathes and so on... What works for one engine may not work on another so its better to start on the safe side.

175's can be a bit more fussy than 125's because of the bigger bore so its something you need to set as accurately and consistently as you can.

Mick

thanks mick , i'll be having a go later this afternoon , work load / time permitting so i'll give the timing an adjust ,

dansofield550 wrote:

Hello Ned , its a temp idea as the silicone hose I used to mount the carb is too flexy for its
Own good , I' ll be making the manifold again with a lip to help trap the hose on.

Thanks for clearing that up Dan. I guessed you would have a good reason for doing it.

thought this may be useful :-

Allens perfomance products who are also on line /google them they manily specialisein Mikuni's but they do a manifold that will bolt to the barrel directly and your carb will fit into it its rubber and very short, it also makes the inlet tract a lot shorter for your Amal about 7 inches to back of belmouth, a lot shorter than you currently have !.

they do a number of different stud centre items so check out the drawings on line or just ring them the owner has raced a Bantam and still has his 175 racer. I can not remeber his name ?

regards Derek

Hello Derek,
The inlet is a length is something I was told about, very important to tune this length , computer simulations led to this , it my look longer in the picture as the engine Isnt on the original mounts, it seems an improvement over my original attempt that was very short . Of voided the proof is in the testing , got my or6 forms and all filled in, hopefully I'll get a space

does anyone know if the ducati energia ignitions have a retarding curve built into them?

At last tank welded and all straped on, I tried changing the timing mick to the 1.6 but it ran
What I can only describe as fuffy and unresponsive

Well even a poor result means you know a bit more about your engine's characteristics.

More advance brings more low end punch so nudge it back up a little and try again.

I don't know how easy it is to adjust but as you get higher its good to keep the change small say 0.15mm.

Then when it's responding better, I'd keep it there until you have the chance of a full bore run.

Mick

Got my entry for sat and Sunday Lydden , parade Laps till I'm happy with the bike , just like to say thankyou to all who help on
the forum, without hits and kind advice and generosity of giving I'd be a long way off from where I am now,
Im looking forward to getting out , just hope the rain stops long enough or it could be wet suit and flippers !

Hi Dan,

Glad to hear you got your entry, if you don't mind me asking what settings are you using with your carb?


Kind Regards

Eddie