Thundermax tuning

B

Bhay2149

Registered User
Hi I’ve currently got a M8 FLFBS Fatboy which is stage 2 with a S&S 465 cam. After the cam was fitted I changed tuners to a Thundermax. My issue is that the bike is pretty poor at low RPMs or constant slow speed. It bucks and jerks a fair bit. I’ve had the plugs and leads changed and don’t seem to have an intake leak.
I’m wondering if anyone has any input on timing or AFR I can try with the Thundermax. I’ve done a good few hundred miles with Auto tune which did help a bit but the issue seems to be intermittent. Some have said it’s the cam but others have said they have same set up and ride is smooth so I’ve come to as for any Thundermax gurus for advise please 🙏
 
Steve at Twin City in South Shields can advise he set my CVO up a few years ago with a Thundermax and stage 2 and he knows a thing or 2 about Thundermax give him a call just tell him that I said to ask him for his advice he is a top man
 
Bhay2149 said:
Hi I’ve currently got a M8 FLFBS Fatboy which is stage 2 with a S&S 465 cam. After the cam was fitted I changed tuners to a Thundermax. My issue is that the bike is pretty poor at low RPMs or constant slow speed. It bucks and jerks a fair bit. I’ve had the plugs and leads changed and don’t seem to have an intake leak.
I’m wondering if anyone has any input on timing or AFR I can try with the Thundermax. I’ve done a good few hundred miles with Auto tune which did help a bit but the issue seems to be intermittent. Some have said it’s the cam but others have said they have same set up and ride is smooth so I’ve come to as for any Thundermax gurus for advise please 🙏
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It won’t be the cam causing the low speed running issues. I put a 465 in an M8 Street Glide and when set up right, its not lumpy at the bottom end and produces very strong torque from around 1500rpm. The 465 is a great cam in an M8 producing smooth useable power all the way to the redline. If it were a 475 that had been fitted, I’d understand comments about a lumpy bottom end power delivery because they are notorious for needing an experienced dyno operator to get them to run properly at low revs. The stock ecu with a remap would have coped well with a 465.

If Autotune isn’t producing a decent tune, it’s probably time to find a good dyno operator who knows Thundermax well and pay for a dyno tune.
 
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Ok cheers, yes that’s ideally what I want someone to look at my map and sort it out. I’m I right that Thundermax only auto tunes the AFR and not timing? I’ll try Steve see if he can help, cheers for your responses
 
Bhay2149 said:
Ok cheers, yes that’s ideally what I want someone to look at my map and sort it out. I’m I right that Thundermax only auto tunes the AFR and not timing? I’ll try Steve see if he can help, cheers for your responses
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I think they only tune the AFR but Steve will confirm this for you, I'm led to believe that when the M8 first appeared Thundermax didn't have a Tuner that the M8 could handle. When Steve fitted a Max plus cams to my CVO Springer it was brilliant so responsive and uncredibly quick so would I have another Max well I would have one above any other
 
Steve prefers a conversation over the phone he can at least listen and advice. So if you ring Twin City at South Shields he should be there now, he can really set the Thundermax up, just tell him Army recommended him you may even get discount
 
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