The 42 will cough on cold start and the decel pop is to be expected as long as it isn't outside of hard throttle decels. You will also notice that you might need to choke after 20 min sitting and run a half a block like that. We told you would like it go back to the article I think it explains how to check the TPS resistance. AHH man not again just when you thought you had it. Keep on pluggin as far as the pms I have been told to take it in till the engine stumbles and then out till it is smooth on a warm engine by 1/4 increments.
Only thing I question is the needle it is the leanest they have.Does it seem like the bike is running hot to you?

smhowse wrote:
Went for a ride again tonight it was about 50 degrees so not too cold. I rode about 30 miles freeway avg 75mph then down a curvy road to my house, riding hard 3 & 4 gear there was a lot of poping on decel.

I did put the #50 nozzle in.
I didn't do anything to the tps resistance.... I just bolted it on and thats it
I have the PMS to about 3/4 turns out now. It seems a little better. I'm going to take it out again tomorrow for a good ride during the day (70-80's) I will pick up some starter fluid too.

I soldered the manifold vacuum port closed and put a rubber boot on it too.

Except for the popping on decel it runs really good.

Man, I will say it sure adds some power and she sounds like a race car now!

Steven

50 deg, thats still kind of on the kool side, a good ten minutes till the engine is at proper op temps. at 3/4 turns, that would require a step up on pilot jet, sounds more like an air leak to me. I don't know of anyone that has had to go up in pilot jet. Didn't you have Ken (mucker) do the tps? If so, probably not an issue as far as where it is set at, just trying to cover all bases. which pipes you running? with baffles or without? Still decel pops after fully warm? decel pops from a slow rate (30, 35mph) or from a high speed (50 + mph) It's hard to tune an engine this time year (winter)

maybe i missed it, but is there a correct part/model number for use for the roadstar - pumpless?

There is no part number for the HSR42 unless you buy the Speedster one from Yamaha. Maxair Engineering sells a kit setup that you can buy with the correct cables, tps mod etc. if you don't want to mess with it.
Otherwise just find a Mikuni HSR42 carb, mod it for the tps or add voes and you are good to go.....er so to speak....I'm still working on it

Steven

Erbman02 wrote:
50 deg, thats still kind of on the kool side, a good ten minutes till the engine is at proper op temps. at 3/4 turns, that would require a step up on pilot jet, sounds more like an air leak to me. I don't know of anyone that has had to go up in pilot jet. Didn't you have Ken (mucker) do the tps? If so, probably not an issue as far as where it is set at, just trying to cover all bases. which pipes you running? with baffles or without? Still decel pops after fully warm? decel pops from a slow rate (30, 35mph) or from a high speed (50 + mph) It's hard to tune an engine this time year (winter)

I did the TPS myself with an article I found so I might need to tweak it. I read a discussion you had on the RSR forum about the TPS and checking it and my head hurts now
I havn't got the starter fluid yet to check for an air leak I doubt it's leaking from the manifold to the heads cause I dremeled out the notches and put oversized o-rings AND gasket sealer. maybe at the carb to manifold but it's really tight I trimmed the notch and tightened the clamp good.

I'm running V&H powershots with baffles (powershots have crossover)

Decel pops from lower speeds 30-40 not from high speed 50+

@ Makcap - The motor does not seem to be running hot

Steven

smhowse wrote:


I did the TPS myself with an article I found so I might need to tweak it. I read a discussion you had on the RSR forum about the TPS and checking it and my head hurts now
I havn't got the starter fluid yet to check for an air leak I doubt it's leaking from the manifold to the heads cause I dremeled out the notches and put oversized o-rings AND gasket sealer. maybe at the carb to manifold but it's really tight I trimmed the notch and tightened the clamp good.

I'm running V&H powershots with baffles (powershots have crossover)

Decel pops from lower speeds 30-40 not from high speed 50+

@ Makcap - The motor does not seem to be running hot

Steven


I set my tps at 720 ohms. What I found when the screws were not tight and turning the tps to achieve the 720 ohm, but after securing the screws tight the resistance dropped considerably. It doesn't take much movement of the tps to see a 100 ohm change. I think I started close to 800 ohms tps loose, then when tighten down ohms dropped to where I wanted it. was very consistent that the ohms were higher when the tps was loose and dropped down when screws were tightened. I just had to replace my gasket on the manifold last week, they were old and dried up, carb cleaner did not show any sign of a leak for some odd reason, had always worked before, I had talked to Joel (odo) and he mentioned to use the starter fluid since it is more volatile than carb cleaner. Sure enough had a leak at bottom on rear jug and a leak on top on front jug. I did away with the o-rings and made my own with 1/8 thick gasket material that I picked up at a speed shop. As far as tps, just make sure that at closed throttle you are getting around 650 to 750 ohm from yellow to black if the tps is on cable guide side? resistance should increase as throttle is applied.

OK I've really mastered the removal of the tank now timed myself 4min flat!

I tested the black and yellow wires and it read 435ohms Now I adjusted the tps and it reads 756ohms when the screws are tight. Am I ok or do I need exactly 700? It does increase as I roll on the throttle.

Steven

Sloe poke 2 min you can do it!

Sound like you are getting it dialed in. So does it ride like we told you it would?

thats fine where it is. the 435 is way too low and that's probably what was causing the low speed excessive popping. should have been noticeable at idle, but think you covered it up a little bit with the rich pilot screw setting. will probably be able to go to closer to 2 turns out now that the timing is better. since the spark was firing way to early, took more gas in the chamber. You should see a marked improvement.

I moved the TPS again and checked it 699-701 checked float level good at 19mm
It's too late to ride tonight so I will ride to work tomorrow and see how it is.

Steven