Seeley (replica) Framed Project Road Racer

[Zunspec4]

I like the light weight hangers for your chambers

I was going to use duct tape but went for the high tech solution.

[Zunspec4]

A photo of the just about finished Seeley



About 15 minutes later it was running

Cheers Geoff

(I won't mention that I dropped it bump starting )

(That Tank/Seat line still needs some attention)

[oldjapanesebikes]

Nicely done !

[Zunspec4]

All I need now is a race track



Cheers Geoff

[CJF]

Looks awesome. Great job with this build. How about a video...would like to hear it run.

[Zunspec4]

Hi Chris,

I'll get a vid of it running soon. It has run already but I did not get the chance to run the camera as I was sorting out the oil pump etc. It does sound sweet though .

I am hoping to enter it for the "parade" slots at the next CRMC meeting at Pembury (Wales, UK) as a shake down session. I am suffering no illusions that the project is finished, in fact you could say it's only just beginning. Contact with enemy, I mean other Racers, is sure to find the weak points and we'll go from there.

Cheers Geoff

[Zunspec4]

I placed front and back wheels on the bathroom scales last night to get a rough estimation of the weight of the beast

Front = 60Kg
Rear = 62Kg

AUW = 122Kg (approx. 268 lbs)

If only my fat ass didn't add considerably to that

Cheers Geoff

[CJF]

That is like a 100 pound reduction from a stock T500, isn't it? That bike should fly with plain old stock engine let alone having the mods you have done. It's going to be run to ride!!!

[Zunspec4]

I have been going lock wire crazy with one of those special set of pliers, this will include lock wiring the chain split link which is something I had not heard about until a few days ago. I hope to be able to take it down to a local Dyno next week, the "Proof of the Pudding" as they say will then be revealed. I am hoping to see amazing power and torque on the other hand I am also prepared to be somewhat deflated. Someone I know who is racing a T500 based bike is only getting low 50's bhp at the back wheel so tales of 70+ bhp might be hard to match.

Cheers Geoff

[Suzukidave]

That sure did come out nice and "classic " looking , be sure your dyno guy is good with testing 2 strokes as i have believe i read that specially on the after run dont let the dyno push the engine at hi rev's with closed throttles .. i hope one of the list guys that knows for sure about this will comment .

[Zunspec4]

Hello Dave,

I understand about the high revs/closed throttle issue (I think ). I hope that it should not be too much of a problem as I will be running with the oil pump controlled from a manual lever on the handlebars. I will set it at Max flow when racing (or dyno'ing) which means when I close the throttle oil will continue to be delivered at full rate, there won't be the sudden loss of lubrication as you would get running with pre-mix.

On the subject of Dyno operators I am somewhat anxious as the ones I have spoken to so far seem to assume I shall be armed with several hundred of GBP (£s) worth of alternative carb parts etc. I first want to do a simple run (some main jets on hand) to determine if I am anywhere in the ball park before shelling out for alternative slide cutaways/needles etc. and experimenting with the ignition setting (starting at 2.9mm BTDC).

All good fun . It will be interesting to see what sort of BHP it will produce when it's current state of porting/pipes/carbs have been optimised. Roll-up, roll-up for T500 BHP guestimate competition

Cheers Geoff

[Suzukidave]

I think what i read had more to do with mixture than oiling , when the throttle is closed your engine is running off the pilot jets and at hi revs with the dyno pushing the engine i think they article said watch for lean out and seizure . Like i said though it has been a long time ago i read this so i hope one of the guys that knows for sure with chime in

[tz375]

Dave is right that the dyno must have a brake and electric starter. The latter makes it much easier than bump starting and then trying to tie it down.

The brake is because the drum on a rolling road dyno can keep the bike spinning at peak revs for a long time with no engine braking to slow it down.

Slides and needles are not going to be needed on the dyno. It's all about WOT and that's really the main jets. Needle jets and needles also have an impact but I'd get a baseline on the dyno and get the main jets close and then ride it at a track day and get the part throttle right by feel and response at the track.

In theory, it's possible to do a complete mapping on a dyno but you need to be able to run at different throttle settings and the normal way is with TPS to record the throttle position but we're talking analogue systems here not a modern digital EFI system.

[Zunspec4]

Hi Guys,

I believe we are thinking along the same lines Ref. the transition to a closed throttle with the engine still spinning at high revs. However you view it the engine suddenly has a loss of mixture (containing all that precious lubrication).

Dyno operators - They have me a bit tied up I must admit . I have spoken to one who went into "3D mapping" and altering stuff to get the best power. I'm thinking "unless you intend to get the porting equipment out and re-design and weld up new pipes we aren't going far mate" . With the porting/pipes as they stand all that can be done is ignition point and jetting. Another chap spoke of being able to get a rough idea of where the jetting was by analysing the exhaust gas as the engine was revved up under no load, how the heck that checks out confuses the heck out of me as by the time you get to full throttle the pistons and rods would be on the outside .

I have initially set the timing at 2.9mm BTDC, Mr Les Trotter (the alleged original engine builder) spoke to me of arriving at 3.1 - 3.2 mm BTDC after running it at a conservative setting to begin with. I then have supplementary advice from two others that if the dyno man does not monitor the running temperature he doesn't properly understand 2-st dyno-ing. The Powerdynamo advance curve is below, as you can see it is fairly simple. Taking the 0 degree line as your static setting (2.9mm BTDC) it has an advance that reduces to 0 again at 10,000 rpm (the absolute limit for a T500).



As you can see there is not a lot to play with (what the heck is a 3D map anyway). I believe that Powerdynamo can change this curve but it is factory job, no plugging in a Laptop here. If I can arrange it I will visit Tim Blakemore racing on Wednesday for a simple dyno run. (http://www.timblakemoreracing.co.uk/bri ... ntact.html.

Cheers Geoff

[Suzukidave]

Please try to get some video of the pull