2018 Aprilia RS4 50 Euro 4 Upgrade Project

[Berkeley]

Thanks Tora,

Will Pass the info onto her

We were running hard for quite a few hours.. normally its not that hot so your diagnosis could be right, hence letting it cool down and thinking it got better. II'll replace the plug, oil, fuel and if amazon is nice to me then ill get a borescope too and check that one out as well. Was scratching my head as to why it was running fine for a number of hours then suddenly the gremlins put in a performance.

When weve talked about oil pumps on here before that did cross my mind.. For the track and short runs its fine but carrying oil and a mixing container a little impractical when going some distance I feel.

But man what a blast on sunday just bombing it around with a tonne of other bikes on fast twisties!

[kaldis12]

There is propably a carburation issue too! As your bike got higher temperature it was too lean for it. That could be a reason for performance loss.
Also you could try to lower the temp to around 60 °C. That would be pretty optimal for performance and durability.

A borescope could help a lot, as Tora said. If you dont have that, you can pull down the head instead.

[Berkeley]

Decided it was time to take it on the track, very hot day and Amaya did very well considering all of it.

The bike cant keep up with the 125's so in two minds now .. a 125 next year for the road, that can be used for the track as well? put more power into this one? of get a 300/400 for the track only bike? The track is great to push your own limits and the bike but nothing beats free riding at the weekends!!

[Berkeley]

So finally after 7 months and £1200.00 later its finally ready to be sent!! Cant wait to fit it. What a ball ache!!!

So many ups and downs.. from waiting months for parts, bad customer feedback (with them getting shitty about me following up 6 weeks later) to my original shock being stuck at customs for a month.. lets hope it arrives in good time!!

[kaldis12]

Woah that was 7 months already?
Anyway looks cool, but was it worth it?

[Berkeley]

Yes a long time indeed!! Only time will tell. Will send some pics on the install. At the moment I have no idea where the piggy back will mount too and if the brackets they supply will fit as well.
At the time yes it was worth it.. now 7 months on I have better things to spend 1200 on.
Hopefully once installed I'll change my mind

[toratora]

Wow. I will be surprised if it actually fits. I know it wouldn’t fit the previous generation without some mods to the frame.

On the other hand the track day action looks totally awesome!!

[Berkeley]

Cheers Tora,

Yes the track days are a lot of fun, I took the RSV4 on there too to get some skills in.. Im slow as fooook compared to the seasoned guys. Got rid of my chicken wings and didnt stack it so all good!

Looking back at your posts you fitted the cobra 50 to the GPR 50 , I see now you have displayed the shock type in the title 'damping the rear end- a shocking experience'. I saw one on ebay for $150.00. for that price I would had tried it first . JHS racing have unequivocally promised that it will fit. The guy got really arsey when I asked if it will lol lets see how this all pans out.

BTW the red frame on the GPR 50 looks amazing, really makes the bike pop!

[toratora]

I thought you were flying around the track on one of the Ohvales.

Did you see the KTM RC4R they just announced for the Norther Cup? Probably way too much bike for any of us, but it sure is cool to see them making product for that segment.

It’s rather difficult to see in the photos of my 05 GPR (because I didn’t really take proper photos of it), but I had to do major mods to both the frame, and swing arm to get that shock in there. The powder coating even conceals my unorthodox effort making it even harder to detect. As for the shock: the travel was too much, and that had to be modified. Also, I’ve yet to procure a spring matched to my mass. So while it looks great in videos, and says Öhlins on the back, it is far from being a proper setup (yet!).

I do plan to get a proper setup for the Red Rocket bike when the fundage exists, but currently I have to spend so much on the engine that I’m not even ready to think about the shock.

Based on the photo this shock looks like he made a custom unit, but the parts don’t look as Öhlins as I would expect—based on my extremely limited exposure to them. I have four Öhlins laying around the house, and they are mostly older except for the 1199 TTX shock. Now that the 1199 subframe is on the 899 I am more motivated to get the 1199 shock modded for the 899. But that will have to wait until an income stream develops, but I digress.

The Öhlins shocks that I’ve seen have a double locking ring spring tension adjuster, the damping adjuster on the shock is rubberized, and the spring color is more of a mustard. It also looks like the bumper is missing.

Hopefully this will fit right in, and be great.

[Berkeley]

Thanks for the pointers about the shock.. I see what you mean and the anomalies going on.. ' well it has the ohlins sticker on the side!! hahahahah

The gold is a little more bronze also so maybe its just the photo???

There is little point in even bringing it up with him, he will get defensive straight away asking him anything about it.. but yeah it is custom and he could have thought well f' it, ill put a cheap spring on it ??

The guys got my money now so little hope of any come back.

I did ask for some progress pics and would had shared, also would be a good way to dbl check with you guys as well.