Ignition advancer

[tony.mon]

Just a report on the difference an ignition advancer makes.

Fitted the -4 degrees Factory Pro sprocketty thing today. Quite impressed so far.

It's certainly better in terms of throttle response, improved mid range pick up. It's not so steady around 3000 on a steady throttle, though, but I'm fitting a jet kit tomorrow and hope to be able to dial that out.

More reports once the jet kit's in, and then it's time for DDDYYNNNNNNNOOOOOOOOOO!

I'm going to HM racing, in Orpington. They seem to know what there about.

Should do, supplying half the MotoGP and WSB paddock with quickshifters....

But I'm really looking forward to changing jets in their car park, to keep the cost down- but I drop a main jet in the gravel, or something stupid!

[tony.mon]

Right, the jet kit's in.

Boy, those carb springs are a pain!

I fitted the 182 (rear) and 180 (front) mains, and the #50 pilots jets, along with the supplied needles at 4 from the top and adjusted the mixture screws to 2 1/2 out.

So what effect has it made?

Mid range is a lot stronger, a bit more vibration, though, feels pokier and is noisier.

However I also set the TPS properly, metered it and it was almost 900 ohms, should be 500, so had to adjust it. Not so straightforward, as it's fitted with non-tamper screws, but I found that i could easily cut a slot in the heads with a mini hacksaw and got them out, then replaced with 5mm cap heads.

I had to adjust the little "tangs" on the carb to get the settings within the range of adjustment.
Don't know how much of the improvement was down to the TPS reset.

It seems to be hunting, slightly, so I'll ride it for now until I can get it on HM's dyno, hopefully Monday/Tuesday.

Then we'll see how accurate the seat of the pants is!

[Pete.L]

Did the same on mine years ago
Pick up is much quicker

Pete.l

[firestarter1977]

tony

i am interested in setting the tps, i have mentioned it before now but didnt get an answer. i am surprised that it isnt widely discussed as it should improve things imho



regards mark

[tony.mon]

Ok, here's what I did.
(I'm sure there's a thread on here somewhere about it already)

Remove tank, airbox, undo carb clamps and lift them off the inlet rubbers. Disconnect throttle cables from carbs, and then one of the coolant pipes which goes to the rear carb. It's only a spring clip, and very little coolant comes out, so no need to clamp it.

You can now lift the carbs far enough to get to all the parts you'll need.

Locate the TPS on the RH side of the carbs, and note that it's held on by two anti-tamper screws.
Disconnect the electrical connection, and you'll see that the TPS socket has three pins.

Connect an Ohm meter set to <2000 ohms range to it- I found that I needed three hands, so to make it easier slip a couple of small spade terminals on each of the top two terminals- you can poke a probe up these, and it'll stay in securely enough to take readings.

Check the reading- it should be 500 Ohms plus or minus ten- quite a tight tolerance.
Mine was reading 900 odd.

If it needs adjusting:

Using a junior hacksaw, carefully cut a screwdriver slot across each screw head, and undo the screws.
Inside you'll see that the TPS has a plastic tang, which rotates against it's spring, and the carb side has two metal tangs which trap it and cause it to rotate when the throttle is opened and closed.

The TPS has slotted holes for adjustment.

If you're lucky, the TPS can be adjusted so that it's within the correct range using the range of adjustment available in the slotted holes.

I found that when the TPS was in the right place, I couldn't get a screw in, as the hole was beyond the elongated slot.

So, if that's the case, you'll need to CAREFULLY bend both of the metal tangs on the carb side so that the correct setting can be achieved.
Try to work out which way they need to be bent before bending them, if you bend them too much or too many times they'll surely snap.
(I got mine the wrong way first time, though )

Use two new screws- I used cap heads, as the original ones you've cut slots into will rust as you've cut through the plating.

Ride the bike, and check out the difference!

[sirch345]

Interesting stuff Tony, I'll look forward to hearing how it all goes on the dyno

[tony.mon]

Booked at HM racing on Monday 29th June, unless they get an earlier cancellation.

I'll let you all know!

[mik_str]

FWIW I had tried the TPS readjustment on my Storm a few years back (after reading of its near magical transformation properties on the US Superhawk forum). If I remember correctly, the stock setting was just shy of 800 ohms and I proceeded to bring it down to 500. I rode the bike this way for two weeks and noticed that I gained nothing (no added smoothness, response or fuel economy). In fact, the throttle response was noticeably lazier (notably at low rpm and in roll-ons at highway speeds) so I proceeded to move the TPS setting back to where it was from the factory and found the missing zip I had lost. No more TPS adjustment for me...

[tony.mon]

Hindsight being a wonderful thing, what I should have done is do the TPS adjustment on its own- then I could have found out if it made any difference.

But I did it while fitting a FP jet kit, so i have no idea if the TPS setting has actually made a difference.

Wonder why Honda give such a tight tolerance on the setting, but then make it non-adjustable?
Maybe specific to particular countries, so that it matches fuel quality etc?