tps adjustment 08 wr450

[dicko450]

Hi, I am thinking about replacing the ignition on my WR with a Dynotek unit in an attemp to cure the TPS stutter and was wondering if the TPS will need adjusting if I do, and if so how are you supposed to get at the TPS screw while the carb is on the bike as it is directly behind the frame ? Please don't tell me it's a matter of trial and error, I'm just about over taking the carb off ? . Thanks.

[FORMA MOTO]

You adjust the TPS with a TPS setting tool, which you can buy or make.

Search youtube for tons of examples.

You lift the subframe, loosen the carb boots, pull the carb enough to rotate it into position.

You only have to remove the fuel line, nothing else.

Use you manuals resistance ranges to get the values.

It will not cure the partial throttle sutter, however.

The issue is in the mapping; there is a jump rather than a transition from one rpm to the next.

The ignition hunts from one map to the other.

IMHO, unplugging the TPS yields the best results.

Loss of low rpm throttle response can easily be gained back with proper accelerator pump tuning and a CRF450R float bowl and apump cover upgrade, or the R&D Powerbowl II.

Edited January 17, 2013 by Krannie

[dicko450]

Okay cheers for that Krannie, have you had any experience with the Dynotek fs ignitions, do they cure the TPS stutter ?

[William1]

Yes, the Dynotek, Vortex and another one (that name escapes me), do. Do a search here and there are some detailed tests that were done and will tell about the map(s) that worked.

[MANIAC998]

And proper jetting will lessen the "stutter" enough where most people can barely perceive it, at a substantial cost savings I might add.

[GlennR]

The DynaTek unit cured my 08's stutter. It was terrible before, now it's fine. I hated to spend the $, but a guy here had one that he let me test before buying.

It has 4 maps preinstalled. I think #3 was the one that fixed it, but not sure. It is very obvious, because the other 3 do not help.

Edited January 17, 2013 by GlennR

[dicko450]

Thanks for that guys, I've got my jetting pretty close now but stutter is still there ( not too bad but just annoying ). GlennR, did the Dynotek stand up to it's other claims i.e. easier starting, slight power increase ? Also did you adjust the TPS after you installed it ?

Edited January 17, 2013 by dicko450

[GlennR]

Thanks for that guys, I've got my jetting pretty close now but stutter is still there ( not too bad but just annoying ). GlennR, did the Dynotek stand up to it's other claims i.e. easier starting, slight power increase ? Also did you adjust the TPS after you installed it ?

I'd "played" around with the TPS, but don't think I really understood how to do it correctly. It barely rotates when I loosened it. I couldn't tell if it made any difference.

I never had any problems starting my bike before the DynaTek, and I can't really say it increased the power any or not. I've always felt like the WR450 has more than enough power for me.

It seems crazy to have to replace the Yamaha CDI with a $300 aftermarket unit just to get it running correctly, but that's just how it is. I'm just glad that I didn't spend a lot of money trying "everything else" before finally getting the DnyaTek. A clueless mechanic could easily spend $300 just "scratching his head" and getting nowhere... So, I was just happy that it was a simple "plug n play" easy 5 minute fix.

It would be great if DynaTek would let folks test them before buying, but they don't.

btw, I thought it was just the US models with the TPS stutter issue, but I see you're in AU.

Edited January 17, 2013 by GlennR

[dicko450]

Yeah it's a bit weird, some seem to have no issues while others have the stutter, can't explain why that is. I have read some people are able to minimise it by adjusting the TPS so maybe it's to do with variations there ?

I've ordered a Dynotek for mine and I agree it's a pretty expensive item but I'm pretty fussy about these things and if it fixes the issue I'll be happy. Yamaha really should have addressed this.